72331397 has 2 divisors, whose sum is σ = 72331398. Its totient is φ = 72331396.

The previous prime is 72331381. The next prime is 72331403. The reversal of 72331397 is 79313327.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67798756 + 4532641 = 8234^2 + 2129^2 .

It is a cyclic number.

It is not a de Polignac number, because 72331397 - 2⁴ = 72331381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72331327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36165698 + 36165699.

It is an arithmetic number, because the mean of its divisors is an integer number (36165699).

Almost surely, 2^72331397 is an apocalyptic number.

It is an amenable number.

72331397 is a deficient number, since it is larger than the sum of its proper divisors (1).

72331397 is an equidigital number, since it uses as much as digits as its factorization.

72331397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23814, while the sum is 35.

The square root of 72331397 is about 8504.7867110234. The cubic root of 72331397 is about 416.6540596363.

The spelling of 72331397 in words is "seventy-two million, three hundred thirty-one thousand, three hundred ninety-seven".