999999128 has 8 divisors (see below), whose sum is σ = 1874998380. Its totient is φ = 499999560.

The previous prime is 999999113. The next prime is 999999131. The reversal of 999999128 is 821999999.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62499938 + ... + 62499953.

Almost surely, 2^999999128 is an apocalyptic number.

It is an amenable number.

999999128 is a deficient number, since it is larger than the sum of its proper divisors (874999252).

999999128 is a wasteful number, since it uses less digits than its factorization.

999999128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124999897 (or 124999893 counting only the distinct ones).

The product of its digits is 8503056, while the sum is 65.

The square root of 999999128 is about 31622.7628141502. The cubic root of 999999128 is about 999.9997093332. Note that the first 3 decimals are identical.

The spelling of 999999128 in words is "nine hundred ninety-nine million, nine hundred ninety-nine thousand, one hundred twenty-eight".