72520139 has 4 divisors (see below), whose sum is σ = 72688056. Its totient is φ = 72352224.

The previous prime is 72520117. The next prime is 72520141. The reversal of 72520139 is 93102527.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72520139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72520109) 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, 83309 + ... + 84174.

It is an arithmetic number, because the mean of its divisors is an integer number (18172014).

Almost surely, 2^72520139 is an apocalyptic number.

72520139 is a deficient number, since it is larger than the sum of its proper divisors (167917).

72520139 is a wasteful number, since it uses less digits than its factorization.

72520139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167916.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 72520139 is about 8515.8757036490. The cubic root of 72520139 is about 417.0161514408.

The spelling of 72520139 in words is "seventy-two million, five hundred twenty thousand, one hundred thirty-nine".