18969780 has 96 divisors (see below), whose sum is σ = 55496448. Its totient is φ = 4838400.

The previous prime is 18969767. The next prime is 18969781. The reversal of 18969780 is 8796981.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18969781) 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 31 ways as a sum of consecutive naturals, for example, 259824 + ... + 259896.

It is an arithmetic number, because the mean of its divisors is an integer number (578088).

Almost surely, 2^18969780 is an apocalyptic number.

18969780 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 18969780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27748224).

18969780 is an abundant number, since it is smaller than the sum of its proper divisors (36526668).

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

18969780 is a wasteful number, since it uses less digits than its factorization.

18969780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 48.

The square root of 18969780 is about 4355.4310923260. The cubic root of 18969780 is about 266.6986176994.

The spelling of 18969780 in words is "eighteen million, nine hundred sixty-nine thousand, seven hundred eighty".