99993988 has 6 divisors (see below), whose sum is σ = 174989486. Its totient is φ = 49996992.

The previous prime is 99993947. The next prime is 99993991. The reversal of 99993988 is 88939999.

It can be written as a sum of positive squares in only one way, i.e., 62441604 + 37552384 = 7902^2 + 6128^2 .

It is a super-2 number, since 2×99993988² = 19997595272288288, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12499245 + ... + 12499252.

Almost surely, 2^99993988 is an apocalyptic number.

It is an amenable number.

99993988 is a deficient number, since it is larger than the sum of its proper divisors (74995498).

99993988 is a wasteful number, since it uses less digits than its factorization.

99993988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24998501 (or 24998499 counting only the distinct ones).

The product of its digits is 11337408, while the sum is 64.

The square root of 99993988 is about 9999.6993954818. The cubic root of 99993988 is about 464.1495814308.

The spelling of 99993988 in words is "ninety-nine million, nine hundred ninety-three thousand, nine hundred eighty-eight".