681808216 has 16 divisors (see below), whose sum is σ = 1278888840. Its totient is φ = 340771200.

The previous prime is 681808187. The next prime is 681808219. The reversal of 681808216 is 612808186.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681808219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7195 + ... + 37621.

Almost surely, 2^681808216 is an apocalyptic number.

It is an amenable number.

681808216 is a deficient number, since it is larger than the sum of its proper divisors (597080624).

681808216 is a wasteful number, since it uses less digits than its factorization.

681808216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33234 (or 33230 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 681808216 is about 26111.4575617678. The cubic root of 681808216 is about 880.1446972807.

The spelling of 681808216 in words is "six hundred eighty-one million, eight hundred eight thousand, two hundred sixteen".