72125621 has 2 divisors, whose sum is σ = 72125622. Its totient is φ = 72125620.

The previous prime is 72125593. The next prime is 72125687. The reversal of 72125621 is 12652127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72063121 + 62500 = 8489^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 72125621 - 2¹⁰ = 72124597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72125021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36062810 + 36062811.

It is an arithmetic number, because the mean of its divisors is an integer number (36062811).

Almost surely, 2^72125621 is an apocalyptic number.

It is an amenable number.

72125621 is a deficient number, since it is larger than the sum of its proper divisors (1).

72125621 is an equidigital number, since it uses as much as digits as its factorization.

72125621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1680, while the sum is 26.

The square root of 72125621 is about 8492.6804367055. The cubic root of 72125621 is about 416.2585705264.

Adding to 72125621 its reverse (12652127), we get a palindrome (84777748).

The spelling of 72125621 in words is "seventy-two million, one hundred twenty-five thousand, six hundred twenty-one".