21601488555504 has 120 divisors (see below), whose sum is σ = 71023076075952. Its totient is φ = 6042374415360.

The previous prime is 21601488555499. The next prime is 21601488555557. The reversal of 21601488555504 is 40555588410612.

It is a happy number.

21601488555504 is a `hidden beast` number, since 2 + 1 + 6 + 0 + 1 + 4 + 8 + 85 + 5 + 550 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 524491077 + ... + 524532260.

Almost surely, 2^{21601488555504} is an apocalyptic number.

21601488555504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21601488555504 is an abundant number, since it is smaller than the sum of its proper divisors (49421587520448).

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

21601488555504 is a wasteful number, since it uses less digits than its factorization.

21601488555504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1049023375 (or 1049023366 counting only the distinct ones).

The product of its (nonzero) digits is 7680000, while the sum is 54.

The spelling of 21601488555504 in words is "twenty-one trillion, six hundred one billion, four hundred eighty-eight million, five hundred fifty-five thousand, five hundred four".