21655601526416 has 80 divisors (see below), whose sum is σ = 49295744453760. Its totient is φ = 9085759580160.

The previous prime is 21655601526397. The next prime is 21655601526421. The reversal of 21655601526416 is 61462510655612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42263240 + ... + 42772568.

It is an arithmetic number, because the mean of its divisors is an integer number (616196805672).

Almost surely, 2^{21655601526416} is an apocalyptic number.

21655601526416 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21655601526416 is an abundant number, since it is smaller than the sum of its proper divisors (27640142927344).

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

21655601526416 is a wasteful number, since it uses less digits than its factorization.

21655601526416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527944 (or 527938 counting only the distinct ones).

The product of its (nonzero) digits is 2592000, while the sum is 50.

The spelling of 21655601526416 in words is "twenty-one trillion, six hundred fifty-five billion, six hundred one million, five hundred twenty-six thousand, four hundred sixteen".