681435972 has 36 divisors (see below), whose sum is σ = 1968593536. Its totient is φ = 194695920.

The previous prime is 681435943. The next prime is 681435977. The reversal of 681435972 is 279534186.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (681435977) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1351804 + ... + 1352307.

Almost surely, 2^681435972 is an apocalyptic number.

It is an amenable number.

681435972 is an abundant number, since it is smaller than the sum of its proper divisors (1287157564).

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

681435972 is a wasteful number, since it uses less digits than its factorization.

681435972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2704128 (or 2704123 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 681435972 is about 26104.3286065740. The cubic root of 681435972 is about 879.9844918066.

The spelling of 681435972 in words is "six hundred eighty-one million, four hundred thirty-five thousand, nine hundred seventy-two".