663650091 has 20 divisors (see below), whose sum is σ = 1067640112. Its totient is φ = 408399408.

The previous prime is 663650087. The next prime is 663650111. The reversal of 663650091 is 190056366.

663650091 is a `hidden beast` number, since 6 + 63 + 6 + 500 + 91 = 666.

It is not a de Polignac number, because 663650091 - 2² = 663650087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (663650021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 314071 + ... + 316176.

Almost surely, 2^663650091 is an apocalyptic number.

663650091 is a deficient number, since it is larger than the sum of its proper divisors (403990021).

663650091 is a wasteful number, since it uses less digits than its factorization.

663650091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 630272 (or 630263 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 663650091 is about 25761.4070073822. The cubic root of 663650091 is about 872.2608616027.

The spelling of 663650091 in words is "six hundred sixty-three million, six hundred fifty thousand, ninety-one".