999000000666 has 24 divisors (see below), whose sum is σ = 2223000002964. Its totient is φ = 324000000000.

The previous prime is 999000000643. The next prime is 999000000667. The reversal of 999000000666 is 666000000999.

It can be written as a sum of positive squares in 2 ways, for example, as 984232647225 + 14767353441 = 992085^2 + 121521^2 .

999000000666 is a strobogrammatic number because it is the same when read upside-down.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (999000000667) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 749999335 + ... + 750000666.

Almost surely, 2^999000000666 is an apocalyptic number.

999000000666 is an abundant number, since it is smaller than the sum of its proper divisors (1224000002298).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

999000000666 is a wasteful number, since it uses less digits than its factorization.

999000000666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500000046 (or 1500000043 counting only the distinct ones).

The product of its (nonzero) digits is 157464, while the sum is 45.

The spelling of 999000000666 in words is "nine hundred ninety-nine billion, six hundred sixty-six", and thus it is an aban number.