691568828 has 12 divisors (see below), whose sum is σ = 1238391000. Its totient is φ = 337742832.

The previous prime is 691568803. The next prime is 691568831. The reversal of 691568828 is 828865196.

It is a super-2 number, since 2×691568828² = 956534887722587168, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 691568828.

It is a congruent number.

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, 2010203 + ... + 2010546.

It is an arithmetic number, because the mean of its divisors is an integer number (103199250).

Almost surely, 2^691568828 is an apocalyptic number.

It is an amenable number.

691568828 is a deficient number, since it is larger than the sum of its proper divisors (546822172).

691568828 is a wasteful number, since it uses less digits than its factorization.

691568828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4020796 (or 4020794 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 53.

The square root of 691568828 is about 26297.6962489112. The cubic root of 691568828 is about 884.3247972152.

The spelling of 691568828 in words is "six hundred ninety-one million, five hundred sixty-eight thousand, eight hundred twenty-eight".