18511940 has 12 divisors (see below), whose sum is σ = 38875116. Its totient is φ = 7404768.

The previous prime is 18511939. The next prime is 18511943. The reversal of 18511940 is 4911581.

It can be written as a sum of positive squares in 2 ways, for example, as 10125124 + 8386816 = 3182^2 + 2896^2 .

It is not an unprimeable number, because it can be changed into a prime (18511943) 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, 462779 + ... + 462818.

It is an arithmetic number, because the mean of its divisors is an integer number (3239593).

Almost surely, 2^18511940 is an apocalyptic number.

18511940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18511940 is an abundant number, since it is smaller than the sum of its proper divisors (20363176).

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

18511940 is a wasteful number, since it uses less digits than its factorization.

18511940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 925606 (or 925604 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 29.

The square root of 18511940 is about 4302.5504064450. The cubic root of 18511940 is about 264.5355100426.

The spelling of 18511940 in words is "eighteen million, five hundred eleven thousand, nine hundred forty".