21002240100 has 36 divisors (see below), whose sum is σ = 60766482224. Its totient is φ = 5600597280.

The previous prime is 21002240099. The next prime is 21002240101. The reversal of 21002240100 is 104220012.

It is an interprime number because it is at equal distance from previous prime (21002240099) and next prime (21002240101).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21002240101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35003434 + ... + 35004033.

Almost surely, 2^21002240100 is an apocalyptic number.

21002240100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002240100 is an abundant number, since it is smaller than the sum of its proper divisors (39764242124).

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

21002240100 is a wasteful number, since it uses less digits than its factorization.

21002240100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70007484 (or 70007477 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21002240100 its reverse (104220012), we get a palindrome (21106460112).

The spelling of 21002240100 in words is "twenty-one billion, two million, two hundred forty thousand, one hundred".