72717697957 has 4 divisors (see below), whose sum is σ = 72824166720. Its totient is φ = 72611229196.

The previous prime is 72717697891. The next prime is 72717698021. The reversal of 72717697957 is 75979671727.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75979671727 = 7283 ⋅10432469.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72717697957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72717697892 and 72717697901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72717697357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53233357 + ... + 53234722.

It is an arithmetic number, because the mean of its divisors is an integer number (18206041680).

Almost surely, 2^72717697957 is an apocalyptic number.

It is an amenable number.

72717697957 is a deficient number, since it is larger than the sum of its proper divisors (106468763).

72717697957 is a wasteful number, since it uses less digits than its factorization.

72717697957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106468762.

The product of its digits is 81682020, while the sum is 67.

The spelling of 72717697957 in words is "seventy-two billion, seven hundred seventeen million, six hundred ninety-seven thousand, nine hundred fifty-seven".