391120156816 has 75 divisors (see below), whose sum is σ = 806647969533. Its totient is φ = 183716328960.

The previous prime is 391120156783. The next prime is 391120156829. The reversal of 391120156816 is 618651021193.

The square root of 391120156816 is 625396.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 7 ways, for example, as 33707491216 + 357412665600 = 183596^2 + 597840^2 .

It is a Duffinian number.

It is an unprimeable number.

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 in 14 ways as a sum of consecutive naturals, for example, 722957506 + ... + 722958046.

Almost surely, 2^391120156816 is an apocalyptic number.

391120156816 is the 625396-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391120156816

391120156816 is an abundant number, since it is smaller than the sum of its proper divisors (415527812717).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

391120156816 is an frugal number, since it uses more digits than its factorization.

391120156816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1158 (or 560 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 43.

The spelling of 391120156816 in words is "three hundred ninety-one billion, one hundred twenty million, one hundred fifty-six thousand, eight hundred sixteen".