189909900 has 144 divisors (see below), whose sum is σ = 627355680. Its totient is φ = 49248000.

The previous prime is 189909899. The next prime is 189909901. The reversal of 189909900 is 9909981.

189909900 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (189909899) and next prime (189909901).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (189909901) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 98950 + ... + 100850.

Almost surely, 2^189909900 is an apocalyptic number.

189909900 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 189909900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313677840).

189909900 is an abundant number, since it is smaller than the sum of its proper divisors (437445780).

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

189909900 is a wasteful number, since it uses less digits than its factorization.

189909900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1961 (or 1948 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The square root of 189909900 is about 13780.7800940295. The cubic root of 189909900 is about 574.7988206094.

The spelling of 189909900 in words is "one hundred eighty-nine million, nine hundred nine thousand, nine hundred".