72139775 has 6 divisors (see below), whose sum is σ = 89453352. Its totient is φ = 57711800.

The previous prime is 72139747. The next prime is 72139777. The reversal of 72139775 is 57793127.

It is not a de Polignac number, because 72139775 - 2²⁰ = 71091199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72139777) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1442771 + ... + 1442820.

It is an arithmetic number, because the mean of its divisors is an integer number (14908892).

Almost surely, 2^72139775 is an apocalyptic number.

72139775 is a deficient number, since it is larger than the sum of its proper divisors (17313577).

72139775 is a wasteful number, since it uses less digits than its factorization.

72139775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2885601 (or 2885596 counting only the distinct ones).

The product of its digits is 92610, while the sum is 41.

The square root of 72139775 is about 8493.5137016432. The cubic root of 72139775 is about 416.2857977371.

The spelling of 72139775 in words is "seventy-two million, one hundred thirty-nine thousand, seven hundred seventy-five".