18640402 has 16 divisors (see below), whose sum is σ = 30611232. Its totient is φ = 8442720.

The previous prime is 18640399. The next prime is 18640403. The reversal of 18640402 is 20404681.

It is not an unprimeable number, because it can be changed into a prime (18640403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5533 + ... + 8239.

It is an arithmetic number, because the mean of its divisors is an integer number (1913202).

Almost surely, 2^18640402 is an apocalyptic number.

18640402 is a deficient number, since it is larger than the sum of its proper divisors (11970830).

18640402 is a wasteful number, since it uses less digits than its factorization.

18640402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3033.

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 18640402 is about 4317.4531844596. The cubic root of 18640402 is about 265.1460071153.

The spelling of 18640402 in words is "eighteen million, six hundred forty thousand, four hundred two".