681961920 has 56 divisors (see below), whose sum is σ = 2165232144. Its totient is φ = 181856256.

The previous prime is 681961913. The next prime is 681961949. The reversal of 681961920 is 29169186.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 354229 + ... + 356148.

Almost surely, 2^681961920 is an apocalyptic number.

681961920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

681961920 is an abundant number, since it is smaller than the sum of its proper divisors (1483270224).

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

681961920 is a wasteful number, since it uses less digits than its factorization.

681961920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 710397 (or 710387 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 42.

The square root of 681961920 is about 26114.4006249426. The cubic root of 681961920 is about 880.2108310276.

The spelling of 681961920 in words is "six hundred eighty-one million, nine hundred sixty-one thousand, nine hundred twenty".