857881635961 has 27 divisors (see below), whose sum is σ = 1003533535557. Its totient is φ = 731231376120.

The previous prime is 857881635911. The next prime is 857881635971. The reversal of 857881635961 is 169536188758.

The square root of 857881635961 is 926219.

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

It is not a de Polignac number, because 857881635961 - 2⁷ = 857881635833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (857881635911) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1990444416 + ... + 1990444846.

Almost surely, 2^857881635961 is an apocalyptic number.

857881635961 is the 926219-th square number.

857881635961 is the 463110-th centered octagonal number.

It is an amenable number.

857881635961 is a deficient number, since it is larger than the sum of its proper divisors (145651899596).

857881635961 is an frugal number, since it uses more digits than its factorization.

857881635961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1490 (or 745 counting only the distinct ones).

The product of its digits is 87091200, while the sum is 67.

The spelling of 857881635961 in words is "eight hundred fifty-seven billion, eight hundred eighty-one million, six hundred thirty-five thousand, nine hundred sixty-one".