63668691 has 12 divisors (see below), whose sum is σ = 93923232. Its totient is φ = 41542416.

The previous prime is 63668653. The next prime is 63668701. The reversal of 63668691 is 19686636.

63668691 is a `hidden beast` number, since 636 + 6 + 8 + 6 + 9 + 1 = 666.

It is not a de Polignac number, because 63668691 - 2¹¹ = 63666643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (63661691) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 74836 + ... + 75681.

It is an arithmetic number, because the mean of its divisors is an integer number (7826936).

Almost surely, 2^63668691 is an apocalyptic number.

63668691 is a deficient number, since it is larger than the sum of its proper divisors (30254541).

63668691 is a wasteful number, since it uses less digits than its factorization.

63668691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150570 (or 150567 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 63668691 is about 7979.2663196562. The cubic root of 63668691 is about 399.3085784459.

The spelling of 63668691 in words is "sixty-three million, six hundred sixty-eight thousand, six hundred ninety-one".