681316697 has 4 divisors (see below), whose sum is σ = 682421556. Its totient is φ = 680211840.

The previous prime is 681316693. The next prime is 681316717. The reversal of 681316697 is 796613186.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 183982096 + 497334601 = 13564^2 + 22301^2 .

It is a cyclic number.

It is not a de Polignac number, because 681316697 - 2² = 681316693 is a prime.

It is a super-2 number, since 2×681316697² = 928384883221979618, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681316693) 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, 551504 + ... + 552737.

It is an arithmetic number, because the mean of its divisors is an integer number (170605389).

Almost surely, 2^681316697 is an apocalyptic number.

It is an amenable number.

681316697 is a deficient number, since it is larger than the sum of its proper divisors (1104859).

681316697 is a wasteful number, since it uses less digits than its factorization.

681316697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1104858.

The product of its digits is 326592, while the sum is 47.

The square root of 681316697 is about 26102.0439238003. The cubic root of 681316697 is about 879.9331461781.

The spelling of 681316697 in words is "six hundred eighty-one million, three hundred sixteen thousand, six hundred ninety-seven".