99999660 has 48 divisors (see below), whose sum is σ = 294739200. Its totient is φ = 25262784.

The previous prime is 99999643. The next prime is 99999677. The reversal of 99999660 is 6699999.

It is an interprime number because it is at equal distance from previous prime (99999643) and next prime (99999677).

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 99999660.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 42720 + ... + 44999.

It is an arithmetic number, because the mean of its divisors is an integer number (6140400).

Almost surely, 2^99999660 is an apocalyptic number.

It is an amenable number.

99999660 is an abundant number, since it is smaller than the sum of its proper divisors (194739540).

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

99999660 is a wasteful number, since it uses less digits than its factorization.

99999660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87750 (or 87748 counting only the distinct ones).

The product of its (nonzero) digits is 2125764, while the sum is 57.

The square root of 99999660 is about 9999.9829999855. The cubic root of 99999660 is about 464.1583573139.

The spelling of 99999660 in words is "ninety-nine million, nine hundred ninety-nine thousand, six hundred sixty".