10215938721 has 16 divisors (see below), whose sum is σ = 14109557760. Its totient is φ = 6567093120.

The previous prime is 10215938693. The next prime is 10215938743. The reversal of 10215938721 is 12783951201.

It is a happy number.

It is not a de Polignac number, because 10215938721 - 2⁹ = 10215938209 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 10215938721.

It is not an unprimeable number, because it can be changed into a prime (10215938771) 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, 10945 + ... + 143358.

It is an arithmetic number, because the mean of its divisors is an integer number (881847360).

Almost surely, 2^10215938721 is an apocalyptic number.

It is an amenable number.

10215938721 is a deficient number, since it is larger than the sum of its proper divisors (3893619039).

10215938721 is a wasteful number, since it uses less digits than its factorization.

10215938721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155096.

The product of its (nonzero) digits is 30240, while the sum is 39.

The spelling of 10215938721 in words is "ten billion, two hundred fifteen million, nine hundred thirty-eight thousand, seven hundred twenty-one".