8131681857 has 32 divisors (see below), whose sum is σ = 11808276480. Its totient is φ = 4947808320.

The previous prime is 8131681853. The next prime is 8131681861. The reversal of 8131681857 is 7581861318.

It is an interprime number because it is at equal distance from previous prime (8131681853) and next prime (8131681861).

It is not a de Polignac number, because 8131681857 - 2² = 8131681853 is a prime.

It is a super-2 number, since 2×8131681857² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (8131681853) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1537744 + ... + 1543022.

It is an arithmetic number, because the mean of its divisors is an integer number (369008640).

Almost surely, 2^8131681857 is an apocalyptic number.

It is an amenable number.

8131681857 is a deficient number, since it is larger than the sum of its proper divisors (3676594623).

8131681857 is a wasteful number, since it uses less digits than its factorization.

8131681857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5733.

The product of its digits is 322560, while the sum is 48.

The square root of 8131681857 is about 90175.8385433704. The cubic root of 8131681857 is about 2010.9138239762.

The spelling of 8131681857 in words is "eight billion, one hundred thirty-one million, six hundred eighty-one thousand, eight hundred fifty-seven".