72909968 has 10 divisors (see below), whose sum is σ = 141263094. Its totient is φ = 36454976.

The previous prime is 72909961. The next prime is 72909997. The reversal of 72909968 is 86990927.

It can be written as a sum of positive squares in only one way, i.e., 72726784 + 183184 = 8528^2 + 428^2 .

It is a super-2 number, since 2×72909968² = 10631726867522048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72909961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2278421 + ... + 2278452.

Almost surely, 2^72909968 is an apocalyptic number.

It is an amenable number.

72909968 is a deficient number, since it is larger than the sum of its proper divisors (68353126).

72909968 is a wasteful number, since it uses less digits than its factorization.

72909968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4556881 (or 4556875 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 50.

The square root of 72909968 is about 8538.7333955336. The cubic root of 72909968 is about 417.7620342222.

The spelling of 72909968 in words is "seventy-two million, nine hundred nine thousand, nine hundred sixty-eight".