681699897 has 24 divisors (see below), whose sum is σ = 1033007040. Its totient is φ = 432603360.

The previous prime is 681699869. The next prime is 681699899. The reversal of 681699897 is 798996186.

It is a de Polignac number, because none of the positive numbers 2^k-681699897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (681699899) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 138 + ... + 36924.

It is an arithmetic number, because the mean of its divisors is an integer number (43041960).

Almost surely, 2^681699897 is an apocalyptic number.

It is an amenable number.

681699897 is a deficient number, since it is larger than the sum of its proper divisors (351307143).

681699897 is a wasteful number, since it uses less digits than its factorization.

681699897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36893 (or 36890 counting only the distinct ones).

The product of its digits is 11757312, while the sum is 63.

The square root of 681699897 is about 26109.3833132841. The cubic root of 681699897 is about 880.0980852274.

The spelling of 681699897 in words is "six hundred eighty-one million, six hundred ninety-nine thousand, eight hundred ninety-seven".