77815668 has 24 divisors (see below), whose sum is σ = 207508672. Its totient is φ = 22233024.

The previous prime is 77815667. The next prime is 77815721. The reversal of 77815668 is 86651877.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77815667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 463105 + ... + 463272.

Almost surely, 2^77815668 is an apocalyptic number.

It is an amenable number.

77815668 is an abundant number, since it is smaller than the sum of its proper divisors (129693004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77815668 is a wasteful number, since it uses less digits than its factorization.

77815668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 926391 (or 926389 counting only the distinct ones).

The product of its digits is 564480, while the sum is 48.

The square root of 77815668 is about 8821.3189490008. The cubic root of 77815668 is about 426.9290267368.

The spelling of 77815668 in words is "seventy-seven million, eight hundred fifteen thousand, six hundred sixty-eight".