18638480 has 80 divisors (see below), whose sum is σ = 50246784. Its totient is φ = 6297600.

The previous prime is 18638467. The next prime is 18638509. The reversal of 18638480 is 8483681.

It is a tau number, because it is divible by the number of its divisors (80).

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, 46280 + ... + 46680.

Almost surely, 2^18638480 is an apocalyptic number.

18638480 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 18638480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25123392).

18638480 is an abundant number, since it is smaller than the sum of its proper divisors (31608304).

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

18638480 is a wasteful number, since it uses less digits than its factorization.

18638480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504 (or 498 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 38.

The square root of 18638480 is about 4317.2305937951. The cubic root of 18638480 is about 265.1368937900.

The spelling of 18638480 in words is "eighteen million, six hundred thirty-eight thousand, four hundred eighty".