861045831 has 6 divisors (see below), whose sum is σ = 1243732880. Its totient is φ = 574030548.

The previous prime is 861045793. The next prime is 861045841. The reversal of 861045831 is 138540168.

861045831 is a `hidden beast` number, since 8 + 610 + 4 + 5 + 8 + 31 = 666.

It is not a de Polignac number, because 861045831 - 2¹⁷ = 860914759 is a prime.

It is a super-2 number, since 2×861045831² = 1482799846164961122, 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 (861045841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47835871 + ... + 47835888.

Almost surely, 2^861045831 is an apocalyptic number.

861045831 is a deficient number, since it is larger than the sum of its proper divisors (382687049).

861045831 is a wasteful number, since it uses less digits than its factorization.

861045831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95671765 (or 95671762 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 861045831 is about 29343.5824500009. The cubic root of 861045831 is about 951.3538705694.

Adding to 861045831 its reverse (138540168), we get a palindrome (999585999).

The spelling of 861045831 in words is "eight hundred sixty-one million, forty-five thousand, eight hundred thirty-one".