72668857 has 4 divisors (see below), whose sum is σ = 72697636. Its totient is φ = 72640080.

The previous prime is 72668837. The next prime is 72668879. The reversal of 72668857 is 75886627.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 46566976 + 26101881 = 6824^2 + 5109^2 .

It is a cyclic number.

It is not a de Polignac number, because 72668857 - 2¹⁵ = 72636089 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72668857.

It is not an unprimeable number, because it can be changed into a prime (72668807) 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, 10194 + ... + 15787.

It is an arithmetic number, because the mean of its divisors is an integer number (18174409).

Almost surely, 2^72668857 is an apocalyptic number.

It is an amenable number.

72668857 is a deficient number, since it is larger than the sum of its proper divisors (28779).

72668857 is a wasteful number, since it uses less digits than its factorization.

72668857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28778.

The product of its digits is 1128960, while the sum is 49.

The square root of 72668857 is about 8524.6030406113. The cubic root of 72668857 is about 417.3010169669.

The spelling of 72668857 in words is "seventy-two million, six hundred sixty-eight thousand, eight hundred fifty-seven".