72539161 has 2 divisors, whose sum is σ = 72539162. Its totient is φ = 72539160.

The previous prime is 72539149. The next prime is 72539167. The reversal of 72539161 is 16193527.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62015625 + 10523536 = 7875^2 + 3244^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72539161 is a prime.

It is equal to p_4258609 and since 72539161 and 4258609 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (72539167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36269580 + 36269581.

It is an arithmetic number, because the mean of its divisors is an integer number (36269581).

Almost surely, 2^72539161 is an apocalyptic number.

It is an amenable number.

72539161 is a deficient number, since it is larger than the sum of its proper divisors (1).

72539161 is an equidigital number, since it uses as much as digits as its factorization.

72539161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11340, while the sum is 34.

The square root of 72539161 is about 8516.9924856137. The cubic root of 72539161 is about 417.0526093033.

The spelling of 72539161 in words is "seventy-two million, five hundred thirty-nine thousand, one hundred sixty-one".