21641352100 has 81 divisors (see below), whose sum is σ = 48135966627. Its totient is φ = 8445290880.

The previous prime is 21641352097. The next prime is 21641352107. The reversal of 21641352100 is 125314612.

It is a happy number.

The square root of 21641352100 is 147110.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 12157708644 + 9483643456 = 110262^2 + 97384^2 .

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21641352107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 69141544 + ... + 69141856.

Almost surely, 2^21641352100 is an apocalyptic number.

21641352100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21641352100 is the 147110-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21641352100

21641352100 is an abundant number, since it is smaller than the sum of its proper divisors (26494614527).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21641352100 is an equidigital number, since it uses as much as digits as its factorization.

21641352100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

Multiplying 21641352100 by its sum of digits (25), we get a square (541033802500 = 735550²).

21641352100 divided by its sum of digits (25) gives a square (865654084 = 29422²).

Adding to 21641352100 its reverse (125314612), we get a palindrome (21766666712).

The spelling of 21641352100 in words is "twenty-one billion, six hundred forty-one million, three hundred fifty-two thousand, one hundred".