72715257 has 6 divisors (see below), whose sum is σ = 105033162. Its totient is φ = 48476832.

The previous prime is 72715217. The next prime is 72715283. The reversal of 72715257 is 75251727.

It can be written as a sum of positive squares in only one way, i.e., 66243321 + 6471936 = 8139^2 + 2544^2 .

It is not a de Polignac number, because 72715257 - 2¹² = 72711161 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72715217) 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, 4039728 + ... + 4039745.

It is an arithmetic number, because the mean of its divisors is an integer number (17505527).

Almost surely, 2^72715257 is an apocalyptic number.

It is an amenable number.

72715257 is a deficient number, since it is larger than the sum of its proper divisors (32317905).

72715257 is a wasteful number, since it uses less digits than its factorization.

72715257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8079479 (or 8079476 counting only the distinct ones).

The product of its digits is 34300, while the sum is 36.

The square root of 72715257 is about 8527.3241406669. The cubic root of 72715257 is about 417.3898154258.

The spelling of 72715257 in words is "seventy-two million, seven hundred fifteen thousand, two hundred fifty-seven".