18695780 has 48 divisors (see below), whose sum is σ = 41489280. Its totient is φ = 7062528.

The previous prime is 18695779. The next prime is 18695783. The reversal of 18695780 is 8759681.

It is a happy number.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (18695783) 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, 44411 + ... + 44829.

It is an arithmetic number, because the mean of its divisors is an integer number (864360).

Almost surely, 2^18695780 is an apocalyptic number.

18695780 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 18695780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20744640).

18695780 is an abundant number, since it is smaller than the sum of its proper divisors (22793500).

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

18695780 is a wasteful number, since it uses less digits than its factorization.

18695780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548 (or 546 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 44.

The square root of 18695780 is about 4323.8616999159. The cubic root of 18695780 is about 265.4083179622.

The spelling of 18695780 in words is "eighteen million, six hundred ninety-five thousand, seven hundred eighty".