21601553102400 has 168 divisors, whose sum is σ = 71280757721664. Its totient is φ = 5727116748800.

The previous prime is 21601553102387. The next prime is 21601553102407. The reversal of 21601553102400 is 420135510612.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (21601553102407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12176316 + ... + 13837115.

Almost surely, 2^{21601553102400} is an apocalyptic number.

21601553102400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21601553102400 is an abundant number, since it is smaller than the sum of its proper divisors (49679204619264).

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

21601553102400 is a wasteful number, since it uses less digits than its factorization.

21601553102400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26013629 (or 26013614 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The spelling of 21601553102400 in words is "twenty-one trillion, six hundred one billion, five hundred fifty-three million, one hundred two thousand, four hundred".