99656666 has 4 divisors (see below), whose sum is σ = 149485002. Its totient is φ = 49828332.

The previous prime is 99656659. The next prime is 99656681. The reversal of 99656666 is 66665699.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66665699 = 19 ⋅3508721.

It can be written as a sum of positive squares in only one way, i.e., 65141041 + 34515625 = 8071^2 + 5875^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24914165 + ... + 24914168.

Almost surely, 2^99656666 is an apocalyptic number.

99656666 is a deficient number, since it is larger than the sum of its proper divisors (49828336).

99656666 is a wasteful number, since it uses less digits than its factorization.

99656666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49828335.

The product of its digits is 3149280, while the sum is 53.

The square root of 99656666 is about 9982.8185398714. The cubic root of 99656666 is about 463.6270691763.

The spelling of 99656666 in words is "ninety-nine million, six hundred fifty-six thousand, six hundred sixty-six".