91660568 has 8 divisors (see below), whose sum is σ = 171863580. Its totient is φ = 45830280.

The previous prime is 91660567. The next prime is 91660643. The reversal of 91660568 is 86506619.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91660567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5728778 + ... + 5728793.

Almost surely, 2^91660568 is an apocalyptic number.

It is an amenable number.

91660568 is a deficient number, since it is larger than the sum of its proper divisors (80203012).

91660568 is a wasteful number, since it uses less digits than its factorization.

91660568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11457577 (or 11457573 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 41.

The square root of 91660568 is about 9573.9525797865. The cubic root of 91660568 is about 450.8798719064.

The spelling of 91660568 in words is "ninety-one million, six hundred sixty thousand, five hundred sixty-eight".