21006656001560 has 32 divisors (see below), whose sum is σ = 47723859275040. Its totient is φ = 8321083152384.

The previous prime is 21006656001553. The next prime is 21006656001587. The reversal of 21006656001560 is 6510065660012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2549347337 + ... + 2549355576.

It is an arithmetic number, because the mean of its divisors is an integer number (1491370602345).

Almost surely, 2^{21006656001560} is an apocalyptic number.

21006656001560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21006656001560 is an abundant number, since it is smaller than the sum of its proper divisors (26717203273480).

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

21006656001560 is a wasteful number, since it uses less digits than its factorization.

21006656001560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5098703027 (or 5098703023 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 38.

The spelling of 21006656001560 in words is "twenty-one trillion, six billion, six hundred fifty-six million, one thousand, five hundred sixty".