72816139 has 4 divisors (see below), whose sum is σ = 79435800. Its totient is φ = 66196480.

The previous prime is 72816131. The next prime is 72816167. The reversal of 72816139 is 93161827.

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

It is a cyclic number.

It is not a de Polignac number, because 72816139 - 2³ = 72816131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72816098 and 72816107.

It is not an unprimeable number, because it can be changed into a prime (72816131) 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, 3309814 + ... + 3309835.

It is an arithmetic number, because the mean of its divisors is an integer number (19858950).

Almost surely, 2^72816139 is an apocalyptic number.

72816139 is a deficient number, since it is larger than the sum of its proper divisors (6619661).

72816139 is a wasteful number, since it uses less digits than its factorization.

72816139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6619660.

The product of its digits is 18144, while the sum is 37.

The square root of 72816139 is about 8533.2373106577. The cubic root of 72816139 is about 417.5827490849.

The spelling of 72816139 in words is "seventy-two million, eight hundred sixteen thousand, one hundred thirty-nine".