189978000 has 80 divisors (see below), whose sum is σ = 612508416. Its totient is φ = 50659200.

The previous prime is 189977971. The next prime is 189978001. The reversal of 189978000 is 879981.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (189978001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9832 + ... + 21831.

Almost surely, 2^189978000 is an apocalyptic number.

189978000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

189978000 is an abundant number, since it is smaller than the sum of its proper divisors (422530416).

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

189978000 is a wasteful number, since it uses less digits than its factorization.

189978000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31689 (or 31673 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 42.

The square root of 189978000 is about 13783.2507051131. The cubic root of 189978000 is about 574.8675183125.

The spelling of 189978000 in words is "one hundred eighty-nine million, nine hundred seventy-eight thousand".