681612808 has 8 divisors (see below), whose sum is σ = 1278024030. Its totient is φ = 340806400.

The previous prime is 681612803. The next prime is 681612809. The reversal of 681612808 is 808216186.

It can be written as a sum of positive squares in only one way, i.e., 588644644 + 92968164 = 24262^2 + 9642^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (681612803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42600793 + ... + 42600808.

Almost surely, 2^681612808 is an apocalyptic number.

It is an amenable number.

681612808 is a deficient number, since it is larger than the sum of its proper divisors (596411222).

681612808 is a wasteful number, since it uses less digits than its factorization.

681612808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85201607 (or 85201603 counting only the distinct ones).

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

The square root of 681612808 is about 26107.7154879549. The cubic root of 681612808 is about 880.0606053302.

The spelling of 681612808 in words is "six hundred eighty-one million, six hundred twelve thousand, eight hundred eight".