18449940 has 48 divisors (see below), whose sum is σ = 51871680. Its totient is φ = 4899840.

The previous prime is 18449923. The next prime is 18449953. The reversal of 18449940 is 4994481.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19396 + ... + 20324.

It is an arithmetic number, because the mean of its divisors is an integer number (1080660).

Almost surely, 2^18449940 is an apocalyptic number.

18449940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18449940 is an abundant number, since it is smaller than the sum of its proper divisors (33421740).

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

18449940 is a wasteful number, since it uses less digits than its factorization.

18449940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1272 (or 1270 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 18449940 is about 4295.3393346743. The cubic root of 18449940 is about 264.2398531852.

The spelling of 18449940 in words is "eighteen million, four hundred forty-nine thousand, nine hundred forty".