72738979 has 4 divisors (see below), whose sum is σ = 72769984. Its totient is φ = 72707976.

The previous prime is 72738943. The next prime is 72738983. The reversal of 72738979 is 97983727.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97983727 = 41 ⋅2389847.

It is a cyclic number.

It is not a de Polignac number, because 72738979 - 2⁷ = 72738851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72768979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11667 + ... + 16780.

It is an arithmetic number, because the mean of its divisors is an integer number (18192496).

Almost surely, 2^72738979 is an apocalyptic number.

72738979 is a deficient number, since it is larger than the sum of its proper divisors (31005).

72738979 is a wasteful number, since it uses less digits than its factorization.

72738979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31004.

The product of its digits is 1333584, while the sum is 52.

The square root of 72738979 is about 8528.7149676842. The cubic root of 72738979 is about 417.4351990454.

The spelling of 72738979 in words is "seventy-two million, seven hundred thirty-eight thousand, nine hundred seventy-nine".