681889939 has 8 divisors (see below), whose sum is σ = 692010000. Its totient is φ = 671840352.

The previous prime is 681889933. The next prime is 681889951. The reversal of 681889939 is 939988186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 681889939 - 2³ = 681889931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681889931) 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, 2037 + ... + 36985.

It is an arithmetic number, because the mean of its divisors is an integer number (86501250).

Almost surely, 2^681889939 is an apocalyptic number.

681889939 is a deficient number, since it is larger than the sum of its proper divisors (10120061).

681889939 is a wasteful number, since it uses less digits than its factorization.

681889939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35237.

The product of its digits is 6718464, while the sum is 61.

The square root of 681889939 is about 26113.0224026251. The cubic root of 681889939 is about 880.1798612216.

The spelling of 681889939 in words is "six hundred eighty-one million, eight hundred eighty-nine thousand, nine hundred thirty-nine".