189989280 has 384 divisors, whose sum is σ = 762048000. Its totient is φ = 43794432.

The previous prime is 189989251. The next prime is 189989281. The reversal of 189989280 is 82989981.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (189989281) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 954621 + ... + 954819.

It is an arithmetic number, because the mean of its divisors is an integer number (1984500).

Almost surely, 2^189989280 is an apocalyptic number.

189989280 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 189989280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (381024000).

189989280 is an abundant number, since it is smaller than the sum of its proper divisors (572058720).

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

189989280 is a wasteful number, since it uses less digits than its factorization.

189989280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253 (or 239 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 54.

The square root of 189989280 is about 13783.6598913351. The cubic root of 189989280 is about 574.8788957303.

The spelling of 189989280 in words is "one hundred eighty-nine million, nine hundred eighty-nine thousand, two hundred eighty".