72331409 has 2 divisors, whose sum is σ = 72331410. Its totient is φ = 72331408.

The previous prime is 72331403. The next prime is 72331459. The reversal of 72331409 is 90413327.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53217025 + 19114384 = 7295^2 + 4372^2 .

It is a cyclic number.

It is not a de Polignac number, because 72331409 - 2²⁴ = 55554193 is a prime.

It is not a weakly prime, because it can be changed into another prime (72331403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36165704 + 36165705.

It is an arithmetic number, because the mean of its divisors is an integer number (36165705).

Almost surely, 2^72331409 is an apocalyptic number.

It is an amenable number.

72331409 is a deficient number, since it is larger than the sum of its proper divisors (1).

72331409 is an equidigital number, since it uses as much as digits as its factorization.

72331409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 29.

The square root of 72331409 is about 8504.7874165084. The cubic root of 72331409 is about 416.6540826777.

The spelling of 72331409 in words is "seventy-two million, three hundred thirty-one thousand, four hundred nine".