681656398 has 8 divisors (see below), whose sum is σ = 1035427680. Its totient is φ = 336513840.

The previous prime is 681656387. The next prime is 681656399. The reversal of 681656398 is 893656186.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681656399) 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, 2156983 + ... + 2157298.

It is an arithmetic number, because the mean of its divisors is an integer number (129428460).

Almost surely, 2^681656398 is an apocalyptic number.

681656398 is a deficient number, since it is larger than the sum of its proper divisors (353771282).

681656398 is a wasteful number, since it uses less digits than its factorization.

681656398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4314362.

The product of its digits is 1866240, while the sum is 52.

The square root of 681656398 is about 26108.5502852993. The cubic root of 681656398 is about 880.0793652594.

The spelling of 681656398 in words is "six hundred eighty-one million, six hundred fifty-six thousand, three hundred ninety-eight".