715906721 has 2 divisors, whose sum is σ = 715906722. Its totient is φ = 715906720.

The previous prime is 715906691. The next prime is 715906727. The reversal of 715906721 is 127609517.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 672676096 + 43230625 = 25936^2 + 6575^2 .

It is a cyclic number.

It is not a de Polignac number, because 715906721 - 2¹⁸ = 715644577 is a prime.

It is not a weakly prime, because it can be changed into another prime (715906727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 357953360 + 357953361.

It is an arithmetic number, because the mean of its divisors is an integer number (357953361).

Almost surely, 2^715906721 is an apocalyptic number.

It is an amenable number.

715906721 is a deficient number, since it is larger than the sum of its proper divisors (1).

715906721 is an equidigital number, since it uses as much as digits as its factorization.

715906721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26460, while the sum is 38.

The square root of 715906721 is about 26756.4332637966. The cubic root of 715906721 is about 894.5792352357.

The spelling of 715906721 in words is "seven hundred fifteen million, nine hundred six thousand, seven hundred twenty-one".