681720956 has 24 divisors (see below), whose sum is σ = 1364232576. Its totient is φ = 291996720.

The previous prime is 681720937. The next prime is 681720959. The reversal of 681720956 is 659027186.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681720959) 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, 50255 + ... + 62361.

It is an arithmetic number, because the mean of its divisors is an integer number (56843024).

Almost surely, 2^681720956 is an apocalyptic number.

It is an amenable number.

681720956 is an abundant number, since it is smaller than the sum of its proper divisors (682511620).

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

681720956 is a wasteful number, since it uses less digits than its factorization.

681720956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14129 (or 14127 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 681720956 is about 26109.7865943021. The cubic root of 681720956 is about 880.1071477660.

The spelling of 681720956 in words is "six hundred eighty-one million, seven hundred twenty thousand, nine hundred fifty-six".