681984218 has 16 divisors (see below), whose sum is σ = 1038375936. Its totient is φ = 335894160.

The previous prime is 681984217. The next prime is 681984263. The reversal of 681984218 is 812489186.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (681984211) 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, 30680 + ... + 48012.

It is an arithmetic number, because the mean of its divisors is an integer number (64898496).

Almost surely, 2^681984218 is an apocalyptic number.

681984218 is a deficient number, since it is larger than the sum of its proper divisors (356391718).

681984218 is a wasteful number, since it uses less digits than its factorization.

681984218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17629.

The product of its digits is 221184, while the sum is 47.

The square root of 681984218 is about 26114.8275506464. The cubic root of 681984218 is about 880.2204242941.

The spelling of 681984218 in words is "six hundred eighty-one million, nine hundred eighty-four thousand, two hundred eighteen".