999680139 has 18 divisors (see below), whose sum is σ = 1468091508. Its totient is φ = 655506000.

The previous prime is 999680131. The next prime is 999680147. The reversal of 999680139 is 931086999.

It is an interprime number because it is at equal distance from previous prime (999680131) and next prime (999680147).

It is not a de Polignac number, because 999680139 - 2³ = 999680131 is a prime.

It is a super-2 number, since 2×999680139² = 1998720760622118642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (999680131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 18564 + ... + 48414.

Almost surely, 2^999680139 is an apocalyptic number.

999680139 is a deficient number, since it is larger than the sum of its proper divisors (468411369).

999680139 is a wasteful number, since it uses less digits than its factorization.

999680139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29979 (or 29915 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 54.

The square root of 999680139 is about 31617.7187507258. The cubic root of 999680139 is about 999.8933682968.

The spelling of 999680139 in words is "nine hundred ninety-nine million, six hundred eighty thousand, one hundred thirty-nine".