72666628 has 6 divisors (see below), whose sum is σ = 127166606. Its totient is φ = 36333312.

The previous prime is 72666599. The next prime is 72666647. The reversal of 72666628 is 82666627.

It can be written as a sum of positive squares in only one way, i.e., 70257924 + 2408704 = 8382^2 + 1552^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9083325 + ... + 9083332.

Almost surely, 2^72666628 is an apocalyptic number.

It is an amenable number.

72666628 is a deficient number, since it is larger than the sum of its proper divisors (54499978).

72666628 is a wasteful number, since it uses less digits than its factorization.

72666628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18166661 (or 18166659 counting only the distinct ones).

The product of its digits is 290304, while the sum is 43.

The square root of 72666628 is about 8524.4723003832. The cubic root of 72666628 is about 417.2967502447.

Subtracting 72666628 from its reverse (82666627), we obtain a palindrome (9999999).

The spelling of 72666628 in words is "seventy-two million, six hundred sixty-six thousand, six hundred twenty-eight".