999999988 has 24 divisors (see below), whose sum is σ = 1890341600. Its totient is φ = 460136160.

The previous prime is 999999937. The next prime is 1000000007. The reversal of 999999988 is 889999999.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11838 + ... + 46261.

Almost surely, 2^999999988 is an apocalyptic number.

It is an amenable number.

999999988 is a deficient number, since it is larger than the sum of its proper divisors (890341612).

999999988 is a wasteful number, since it uses less digits than its factorization.

999999988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58447 (or 58445 counting only the distinct ones).

The product of its digits is 306110016, while the sum is 79.

The square root of 999999988 is about 31622.7764119471. The cubic root of 999999988 is about 999.9999960000. Note that the first 5 decimals are identical.

The spelling of 999999988 in words is "nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty-eight".