21513015140520 has 64 divisors (see below), whose sum is σ = 64542551440320. Its totient is φ = 5736492391424.

The previous prime is 21513015140453. The next prime is 21513015140521. The reversal of 21513015140520 is 2504151031512.

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 (21513015140521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2647089 + ... + 7073408.

It is an arithmetic number, because the mean of its divisors is an integer number (1008477366255).

Almost surely, 2^{21513015140520} is an apocalyptic number.

21513015140520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21513015140520 is an abundant number, since it is smaller than the sum of its proper divisors (43029536299800).

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

21513015140520 is a wasteful number, since it uses less digits than its factorization.

21513015140520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9738954 (or 9738950 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 30.

The spelling of 21513015140520 in words is "twenty-one trillion, five hundred thirteen billion, fifteen million, one hundred forty thousand, five hundred twenty".