21257103800 has 48 divisors (see below), whose sum is σ = 49932324960. Its totient is φ = 8415175680.

The previous prime is 21257103797. The next prime is 21257103811. The reversal of 21257103800 is 830175212.

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 11 ways as a sum of consecutive naturals, for example, 528464 + ... + 567263.

It is an arithmetic number, because the mean of its divisors is an integer number (1040256770).

Almost surely, 2^21257103800 is an apocalyptic number.

21257103800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21257103800 is an abundant number, since it is smaller than the sum of its proper divisors (28675221160).

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

21257103800 is a wasteful number, since it uses less digits than its factorization.

21257103800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1095840 (or 1095831 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 29.

The spelling of 21257103800 in words is "twenty-one billion, two hundred fifty-seven million, one hundred three thousand, eight hundred".