21229401600 has 540 divisors, whose sum is σ = 83563628148. Its totient is φ = 5143142400.

The previous prime is 21229401581. The next prime is 21229401623. The reversal of 21229401600 is 610492212.

21229401600 is a `hidden beast` number, since 2 + 12 + 2 + 9 + 40 + 1 + 600 = 666.

It is a congruent number.

It is an unprimeable number.

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 53 ways as a sum of consecutive naturals, for example, 13938439 + ... + 13939961.

Almost surely, 2^21229401600 is an apocalyptic number.

21229401600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21229401600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41781814074).

21229401600 is an abundant number, since it is smaller than the sum of its proper divisors (62334226548).

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

21229401600 is a wasteful number, since it uses less digits than its factorization.

21229401600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1579 (or 1544 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

Adding to 21229401600 its reverse (610492212), we get a palindrome (21839893812).

The spelling of 21229401600 in words is "twenty-one billion, two hundred twenty-nine million, four hundred one thousand, six hundred".