681801631 has 18 divisors (see below), whose sum is σ = 819582480. Its totient is φ = 565510680.

The previous prime is 681801607. The next prime is 681801641. The reversal of 681801631 is 136108186.

It is not a de Polignac number, because 681801631 - 2⁷ = 681801503 is a prime.

It is a super-2 number, since 2×681801631² = 929706928068520322, 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 (681801641) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 39850 + ... + 54328.

It is an arithmetic number, because the mean of its divisors is an integer number (45532360).

Almost surely, 2^681801631 is an apocalyptic number.

681801631 is a deficient number, since it is larger than the sum of its proper divisors (137780849).

681801631 is a wasteful number, since it uses less digits than its factorization.

681801631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14555 (or 14517 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 681801631 is about 26111.3314673917. The cubic root of 681801631 is about 880.1418637510.

The spelling of 681801631 in words is "six hundred eighty-one million, eight hundred one thousand, six hundred thirty-one".