189978975 has 18 divisors (see below), whose sum is σ = 340273856. Its totient is φ = 101322000.

The previous prime is 189978973. The next prime is 189979001. The reversal of 189978975 is 579879981.

It is not a de Polignac number, because 189978975 - 2¹ = 189978973 is a prime.

It is a super-3 number, since 3×189978975³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189978973) 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 17 ways as a sum of consecutive naturals, for example, 421951 + ... + 422400.

Almost surely, 2^189978975 is an apocalyptic number.

189978975 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

189978975 is a deficient number, since it is larger than the sum of its proper divisors (150294881).

189978975 is a wasteful number, since it uses less digits than its factorization.

189978975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 844367 (or 844359 counting only the distinct ones).

The product of its digits is 11430720, while the sum is 63.

The square root of 189978975 is about 13783.2860740826. The cubic root of 189978975 is about 574.8685017507.

It can be divided in two parts, 18997 and 8975, that added together give a palindrome (27972).

The spelling of 189978975 in words is "one hundred eighty-nine million, nine hundred seventy-eight thousand, nine hundred seventy-five".