18399402 has 72 divisors (see below), whose sum is σ = 48443616. Its totient is φ = 5022864.

The previous prime is 18399377. The next prime is 18399413. The reversal of 18399402 is 20499381.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 19833 + ... + 20739.

It is an arithmetic number, because the mean of its divisors is an integer number (672828).

Almost surely, 2^18399402 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18399402, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24221808).

18399402 is an abundant number, since it is smaller than the sum of its proper divisors (30044214).

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

18399402 is a wasteful number, since it uses less digits than its factorization.

18399402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 952 (or 942 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 18399402 is about 4289.4524126047. The cubic root of 18399402 is about 263.9983643149.

The spelling of 18399402 in words is "eighteen million, three hundred ninety-nine thousand, four hundred two".