915721012173 has 32 divisors (see below), whose sum is σ = 1389951332352. Its totient is φ = 530821332800.

The previous prime is 915721012109. The next prime is 915721012247. The reversal of 915721012173 is 371210127519.

It is not a de Polignac number, because 915721012173 - 2⁶ = 915721012109 is a prime.

It is a super-2 number, since 2×915721012173² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (915721012673) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20779903 + ... + 20823923.

It is an arithmetic number, because the mean of its divisors is an integer number (43435979136).

Almost surely, 2^915721012173 is an apocalyptic number.

It is an amenable number.

915721012173 is a deficient number, since it is larger than the sum of its proper divisors (474230320179).

915721012173 is a wasteful number, since it uses less digits than its factorization.

915721012173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71465.

The product of its (nonzero) digits is 26460, while the sum is 39.

The spelling of 915721012173 in words is "nine hundred fifteen billion, seven hundred twenty-one million, twelve thousand, one hundred seventy-three".