72515709 has 16 divisors (see below), whose sum is σ = 122778240. Its totient is φ = 41437440.

The previous prime is 72515699. The next prime is 72515741. The reversal of 72515709 is 90751527.

72515709 is a `hidden beast` number, since 72 + 515 + 70 + 9 = 666.

It is not a de Polignac number, because 72515709 - 2⁷ = 72515581 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72515749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 191652 + ... + 192029.

It is an arithmetic number, because the mean of its divisors is an integer number (7673640).

Almost surely, 2^72515709 is an apocalyptic number.

It is an amenable number.

72515709 is a deficient number, since it is larger than the sum of its proper divisors (50262531).

72515709 is a wasteful number, since it uses less digits than its factorization.

72515709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383697 (or 383691 counting only the distinct ones).

The product of its (nonzero) digits is 22050, while the sum is 36.

The square root of 72515709 is about 8515.6155972425. The cubic root of 72515709 is about 417.0076599183.

The spelling of 72515709 in words is "seventy-two million, five hundred fifteen thousand, seven hundred nine".