681810658 has 8 divisors (see below), whose sum is σ = 1027106028. Its totient is φ = 339441984.

The previous prime is 681810641. The next prime is 681810671. The reversal of 681810658 is 856018186.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 628855929 + 52954729 = 25077^2 + 7277^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 731091 + ... + 732022.

Almost surely, 2^681810658 is an apocalyptic number.

681810658 is a deficient number, since it is larger than the sum of its proper divisors (345295370).

681810658 is a wasteful number, since it uses less digits than its factorization.

681810658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1463348.

The product of its (nonzero) digits is 92160, while the sum is 43.

The square root of 681810658 is about 26111.5043228076. The cubic root of 681810658 is about 880.1457480702.

The spelling of 681810658 in words is "six hundred eighty-one million, eight hundred ten thousand, six hundred fifty-eight".