857881631 has 8 divisors (see below), whose sum is σ = 886093824. Its totient is φ = 829703160.

The previous prime is 857881621. The next prime is 857881639. The reversal of 857881631 is 136188758.

It is a happy number.

857881631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 857881631 - 2¹⁸ = 857619487 is a prime.

It is a super-2 number, since 2×857881631² = 1471921785614440322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857881639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49766 + ... + 64748.

It is an arithmetic number, because the mean of its divisors is an integer number (110761728).

Almost surely, 2^857881631 is an apocalyptic number.

857881631 is a deficient number, since it is larger than the sum of its proper divisors (28212193).

857881631 is a wasteful number, since it uses less digits than its factorization.

857881631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16861.

The product of its digits is 322560, while the sum is 47.

The square root of 857881631 is about 29289.6164365462. The cubic root of 857881631 is about 950.1870844845.

It can be divided in two parts, 8578 and 81631, that added together give a palindrome (90209).

The spelling of 857881631 in words is "eight hundred fifty-seven million, eight hundred eighty-one thousand, six hundred thirty-one".