21301557532720 has 20 divisors (see below), whose sum is σ = 49526121263760. Its totient is φ = 8520623013056.

The previous prime is 21301557532691. The next prime is 21301557532733. The reversal of 21301557532720 is 2723575510312.

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133134734500 + ... + 133134734659.

It is an arithmetic number, because the mean of its divisors is an integer number (2476306063188).

Almost surely, 2^{21301557532720} is an apocalyptic number.

21301557532720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21301557532720 is an abundant number, since it is smaller than the sum of its proper divisors (28224563731040).

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

21301557532720 is a wasteful number, since it uses less digits than its factorization.

21301557532720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266269469172 (or 266269469166 counting only the distinct ones).

The product of its (nonzero) digits is 441000, while the sum is 43.

The spelling of 21301557532720 in words is "twenty-one trillion, three hundred one billion, five hundred fifty-seven million, five hundred thirty-two thousand, seven hundred twenty".