21256032253456 has 160 divisors (see below), whose sum is σ = 55351705264128. Its totient is φ = 7636744696320.

The previous prime is 21256032253427. The next prime is 21256032253523. The reversal of 21256032253456 is 65435223065212.

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 31 ways as a sum of consecutive naturals, for example, 15068665 + ... + 16418791.

Almost surely, 2^{21256032253456} is an apocalyptic number.

21256032253456 is a gapful number since it is divisible by the number (26) 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 21256032253456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27675852632064).

21256032253456 is an abundant number, since it is smaller than the sum of its proper divisors (34095673010672).

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

21256032253456 is a wasteful number, since it uses less digits than its factorization.

21256032253456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1351149 (or 1351143 counting only the distinct ones).

The product of its (nonzero) digits is 2592000, while the sum is 46.

The spelling of 21256032253456 in words is "twenty-one trillion, two hundred fifty-six billion, thirty-two million, two hundred fifty-three thousand, four hundred fifty-six".