72171316426517 has 32 divisors (see below), whose sum is σ = 98558021272320. Its totient is φ = 51104159124480.

The previous prime is 72171316426511. The next prime is 72171316426537. The reversal of 72171316426517 is 71562461317127.

It is not a de Polignac number, because 72171316426517 - 2¹⁰ = 72171316425493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72171316426511) 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, 950560238 + ... + 950636159.

It is an arithmetic number, because the mean of its divisors is an integer number (3079938164760).

Almost surely, 2^{72171316426517} is an apocalyptic number.

72171316426517 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

It is an amenable number.

72171316426517 is a deficient number, since it is larger than the sum of its proper divisors (26386704845803).

72171316426517 is a wasteful number, since it uses less digits than its factorization.

72171316426517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1901196461.

The product of its digits is 2963520, while the sum is 53.

The spelling of 72171316426517 in words is "seventy-two trillion, one hundred seventy-one billion, three hundred sixteen million, four hundred twenty-six thousand, five hundred seventeen".