18999992 has 16 divisors (see below), whose sum is σ = 38863800. Its totient is φ = 8636320.

The previous prime is 18999991. The next prime is 18999997. The reversal of 18999992 is 29999981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18999991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107867 + ... + 108042.

Almost surely, 2^18999992 is an apocalyptic number.

It is an amenable number.

18999992 is an abundant number, since it is smaller than the sum of its proper divisors (19863808).

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

18999992 is a wasteful number, since it uses less digits than its factorization.

18999992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215926 (or 215922 counting only the distinct ones).

The product of its digits is 944784, while the sum is 56.

The square root of 18999992 is about 4358.8980258776. The cubic root of 18999992 is about 266.8401274209.

It can be divided in two parts, 189999 and 92, that added together give a palindrome (190091).

The spelling of 18999992 in words is "eighteen million, nine hundred ninety-nine thousand, nine hundred ninety-two".