691703641831 has 4 divisors (see below), whose sum is σ = 695701928952. Its totient is φ = 687705354712.

The previous prime is 691703641757. The next prime is 691703641843. The reversal of 691703641831 is 138146307196.

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

It is a cyclic number.

It is not a de Polignac number, because 691703641831 - 2³⁹ = 141947827943 is a prime.

It is a super-2 number, since 2×691703641831² (a number of 24 digits) 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 (691703641231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1999143301 + ... + 1999143646.

It is an arithmetic number, because the mean of its divisors is an integer number (173925482238).

Almost surely, 2^691703641831 is an apocalyptic number.

691703641831 is a deficient number, since it is larger than the sum of its proper divisors (3998287121).

691703641831 is a wasteful number, since it uses less digits than its factorization.

691703641831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3998287120.

The product of its (nonzero) digits is 653184, while the sum is 49.

The spelling of 691703641831 in words is "six hundred ninety-one billion, seven hundred three million, six hundred forty-one thousand, eight hundred thirty-one".