681660924 has 24 divisors (see below), whose sum is σ = 1817762688. Its totient is φ = 194760240.

The previous prime is 681660923. The next prime is 681660971. The reversal of 681660924 is 429066186.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681660923) 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, 4057422 + ... + 4057589.

It is an arithmetic number, because the mean of its divisors is an integer number (75740112).

Almost surely, 2^681660924 is an apocalyptic number.

It is an amenable number.

681660924 is an abundant number, since it is smaller than the sum of its proper divisors (1136101764).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

681660924 is a wasteful number, since it uses less digits than its factorization.

681660924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8115025 (or 8115023 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 42.

The square root of 681660924 is about 26108.6369617412. The cubic root of 681660924 is about 880.0813130786.

The spelling of 681660924 in words is "six hundred eighty-one million, six hundred sixty thousand, nine hundred twenty-four".