18639430 has 16 divisors (see below), whose sum is σ = 35010144. Its totient is φ = 7131520.

The previous prime is 18639421. The next prime is 18639433. The reversal of 18639430 is 3493681.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18639433) 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, 40291 + ... + 40750.

It is an arithmetic number, because the mean of its divisors is an integer number (2188134).

Almost surely, 2^18639430 is an apocalyptic number.

18639430 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18639430 is a deficient number, since it is larger than the sum of its proper divisors (16370714).

18639430 is a wasteful number, since it uses less digits than its factorization.

18639430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81071.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 18639430 is about 4317.3406166296. The cubic root of 18639430 is about 265.1413983735.

The spelling of 18639430 in words is "eighteen million, six hundred thirty-nine thousand, four hundred thirty".