21002081560 has 16 divisors (see below), whose sum is σ = 47254683600. Its totient is φ = 8400832608.

The previous prime is 21002081549. The next prime is 21002081591. The reversal of 21002081560 is 6518020012.

It is a congruent number.

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, 262525980 + ... + 262526059.

It is an arithmetic number, because the mean of its divisors is an integer number (2953417725).

Almost surely, 2^21002081560 is an apocalyptic number.

21002081560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002081560 is an abundant number, since it is smaller than the sum of its proper divisors (26252602040).

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

21002081560 is a wasteful number, since it uses less digits than its factorization.

21002081560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525052050 (or 525052046 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The spelling of 21002081560 in words is "twenty-one billion, two million, eighty-one thousand, five hundred sixty".