21500231670515 has 16 divisors (see below), whose sum is σ = 27987724382688. Its totient is φ = 15761202951936.

The previous prime is 21500231670503. The next prime is 21500231670557. The reversal of 21500231670515 is 51507613200512.

It is not a de Polignac number, because 21500231670515 - 2²⁶ = 21500164561651 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1207191077 + ... + 1207208886.

It is an arithmetic number, because the mean of its divisors is an integer number (1749232773918).

Almost surely, 2^{21500231670515} is an apocalyptic number.

21500231670515 is a deficient number, since it is larger than the sum of its proper divisors (6487492712173).

21500231670515 is a wasteful number, since it uses less digits than its factorization.

21500231670515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2414400118.

The product of its (nonzero) digits is 63000, while the sum is 38.

The spelling of 21500231670515 in words is "twenty-one trillion, five hundred billion, two hundred thirty-one million, six hundred seventy thousand, five hundred fifteen".