18778880 has 72 divisors (see below), whose sum is σ = 47682432. Its totient is φ = 7061504.

The previous prime is 18778871. The next prime is 18778891. The reversal of 18778880 is 8887781.

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, 21329 + ... + 22191.

It is an arithmetic number, because the mean of its divisors is an integer number (662256).

Almost surely, 2^18778880 is an apocalyptic number.

18778880 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 18778880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23841216).

18778880 is an abundant number, since it is smaller than the sum of its proper divisors (28903552).

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

18778880 is an equidigital number, since it uses as much as digits as its factorization.

18778880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 901 (or 887 counting only the distinct ones).

The product of its (nonzero) digits is 200704, while the sum is 47.

The square root of 18778880 is about 4333.4605109543. The cubic root of 18778880 is about 265.8009704567.

The spelling of 18778880 in words is "eighteen million, seven hundred seventy-eight thousand, eight hundred eighty".