189980644 has 144 divisors (see below), whose sum is σ = 445398912. Its totient is φ = 70253568.

The previous prime is 189980603. The next prime is 189980647. The reversal of 189980644 is 446089981.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (189980647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2835499 + ... + 2835565.

It is an arithmetic number, because the mean of its divisors is an integer number (3093048).

Almost surely, 2^189980644 is an apocalyptic number.

189980644 is a gapful number since it is divisible by the number (14) 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 189980644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222699456).

189980644 is an abundant number, since it is smaller than the sum of its proper divisors (255418268).

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

189980644 is a wasteful number, since it uses less digits than its factorization.

189980644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 49.

The square root of 189980644 is about 13783.3466182927. The cubic root of 189980644 is about 574.8701851873.

The spelling of 189980644 in words is "one hundred eighty-nine million, nine hundred eighty thousand, six hundred forty-four".