999000000642 has 32 divisors (see below), whose sum is σ = 2283459283584. Its totient is φ = 285424732800.

The previous prime is 999000000617. The next prime is 999000000643. The reversal of 999000000642 is 246000000999.

It is a self number, because there is not a number n which added to its sum of digits gives 999000000642.

It is not an unprimeable number, because it can be changed into a prime (999000000643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4835542 + ... + 5037902.

It is an arithmetic number, because the mean of its divisors is an integer number (71358102612).

Almost surely, 2^999000000642 is an apocalyptic number.

999000000642 is an abundant number, since it is smaller than the sum of its proper divisors (1284459282942).

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

999000000642 is a wasteful number, since it uses less digits than its factorization.

999000000642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319914.

The product of its (nonzero) digits is 34992, while the sum is 39.

The spelling of 999000000642 in words is "nine hundred ninety-nine billion, six hundred forty-two", and thus it is an aban number.