18645880 has 64 divisors (see below), whose sum is σ = 47278080. Its totient is φ = 6556800.

The previous prime is 18645871. The next prime is 18645881. The reversal of 18645880 is 8854681.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18645881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12957 + ... + 14323.

It is an arithmetic number, because the mean of its divisors is an integer number (738720).

Almost surely, 2^18645880 is an apocalyptic number.

18645880 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 18645880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23639040).

18645880 is an abundant number, since it is smaller than the sum of its proper divisors (28632200).

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

18645880 is a wasteful number, since it uses less digits than its factorization.

18645880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1420 (or 1416 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 40.

The square root of 18645880 is about 4318.0875396407. The cubic root of 18645880 is about 265.1719780782.

It can be divided in two parts, 1864 and 5880, that added together give a square (7744 = 88²).

The spelling of 18645880 in words is "eighteen million, six hundred forty-five thousand, eight hundred eighty".