851656613 has 4 divisors (see below), whose sum is σ = 851787948. Its totient is φ = 851525280.

The previous prime is 851656607. The next prime is 851656621. The reversal of 851656613 is 316656158.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 522488164 + 329168449 = 22858^2 + 18143^2 .

It is a cyclic number.

It is not a de Polignac number, because 851656613 - 2⁸ = 851656357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (851656913) 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 in 3 ways as a sum of consecutive naturals, for example, 55406 + ... + 69087.

It is an arithmetic number, because the mean of its divisors is an integer number (212946987).

Almost surely, 2^851656613 is an apocalyptic number.

It is an amenable number.

851656613 is a deficient number, since it is larger than the sum of its proper divisors (131335).

851656613 is a wasteful number, since it uses less digits than its factorization.

851656613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131334.

The product of its digits is 129600, while the sum is 41.

The square root of 851656613 is about 29183.1563234685. The cubic root of 851656613 is about 947.8832326790.

The spelling of 851656613 in words is "eight hundred fifty-one million, six hundred fifty-six thousand, six hundred thirteen".