18672640 has 88 divisors (see below), whose sum is σ = 51289632. Its totient is φ = 6389760.

The previous prime is 18672637. The next prime is 18672653. The reversal of 18672640 is 4627681.

It is a junction number, because it is equal to n+sod(n) for n = 18672596 and 18672605.

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, 35580 + ... + 36100.

Almost surely, 2^18672640 is an apocalyptic number.

18672640 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 18672640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25644816).

18672640 is an abundant number, since it is smaller than the sum of its proper divisors (32616992).

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

18672640 is an equidigital number, since it uses as much as digits as its factorization.

18672640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 18672640 is about 4321.1850226529. The cubic root of 18672640 is about 265.2987730267.

The spelling of 18672640 in words is "eighteen million, six hundred seventy-two thousand, six hundred forty".