18997040 has 40 divisors (see below), whose sum is σ = 44715888. Its totient is φ = 7504640.

The previous prime is 18997039. The next prime is 18997061. The reversal of 18997040 is 4079981.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 18996985 and 18997003.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5210 + ... + 8070.

Almost surely, 2^18997040 is an apocalyptic number.

18997040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18997040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22357944).

18997040 is an abundant number, since it is smaller than the sum of its proper divisors (25718848).

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

18997040 is a wasteful number, since it uses less digits than its factorization.

18997040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2957 (or 2951 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 18997040 is about 4358.5593950295. The cubic root of 18997040 is about 266.8263071896.

The spelling of 18997040 in words is "eighteen million, nine hundred ninety-seven thousand, forty".