999940005 has 16 divisors (see below), whose sum is σ = 1777671360. Its totient is φ = 533301264.

The previous prime is 999939991. The next prime is 999940013. The reversal of 999940005 is 500049999.

It is a happy number.

It is not a de Polignac number, because 999940005 - 2¹⁷ = 999808933 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3703347 + ... + 3703616.

It is an arithmetic number, because the mean of its divisors is an integer number (111104460).

Almost surely, 2^999940005 is an apocalyptic number.

It is an amenable number.

999940005 is a deficient number, since it is larger than the sum of its proper divisors (777731355).

999940005 is a wasteful number, since it uses less digits than its factorization.

999940005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7406977 (or 7406971 counting only the distinct ones).

The product of its (nonzero) digits is 131220, while the sum is 45.

The square root of 999940005 is about 31621.8279832144. The cubic root of 999940005 is about 999.9800012667.

The spelling of 999940005 in words is "nine hundred ninety-nine million, nine hundred forty thousand, five".