72171255657507 has 8 divisors (see below), whose sum is σ = 96375704341584. Its totient is φ = 48040488705888.

The previous prime is 72171255657499. The next prime is 72171255657577. The reversal of 72171255657507 is 70575655217127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 72171255657507 - 2³ = 72171255657499 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72171255657577) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18420430828 + ... + 18420434745.

It is an arithmetic number, because the mean of its divisors is an integer number (12046963042698).

Almost surely, 2^{72171255657507} is an apocalyptic number.

72171255657507 is a deficient number, since it is larger than the sum of its proper divisors (24204448684077).

72171255657507 is a wasteful number, since it uses less digits than its factorization.

72171255657507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36840866229.

The product of its (nonzero) digits is 36015000, while the sum is 60.

The spelling of 72171255657507 in words is "seventy-two trillion, one hundred seventy-one billion, two hundred fifty-five million, six hundred fifty-seven thousand, five hundred seven".