18881280 has 216 divisors, whose sum is σ = 71744400. Its totient is φ = 4546560.

The previous prime is 18881273. The next prime is 18881281. The reversal of 18881280 is 8218881.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (18881281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 126646 + ... + 126794.

It is an arithmetic number, because the mean of its divisors is an integer number (332150).

Almost surely, 2^18881280 is an apocalyptic number.

18881280 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 18881280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35872200).

18881280 is an abundant number, since it is smaller than the sum of its proper divisors (52863120).

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

18881280 is a wasteful number, since it uses less digits than its factorization.

18881280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 170 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 36.

The square root of 18881280 is about 4345.2594859226. The cubic root of 18881280 is about 266.2832266937.

The spelling of 18881280 in words is "eighteen million, eight hundred eighty-one thousand, two hundred eighty".