189964947 has 4 divisors (see below), whose sum is σ = 253286600. Its totient is φ = 126643296.

The previous prime is 189964939. The next prime is 189964961. The reversal of 189964947 is 749469981.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 189964947 - 2³ = 189964939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189964967) 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 3 ways as a sum of consecutive naturals, for example, 31660822 + ... + 31660827.

It is an arithmetic number, because the mean of its divisors is an integer number (63321650).

Almost surely, 2^189964947 is an apocalyptic number.

189964947 is a deficient number, since it is larger than the sum of its proper divisors (63321653).

189964947 is an equidigital number, since it uses as much as digits as its factorization.

189964947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63321652.

The product of its digits is 3919104, while the sum is 57.

The square root of 189964947 is about 13782.7771874902. Note that the first 3 decimals coincide. The cubic root of 189964947 is about 574.8543520203.

The spelling of 189964947 in words is "one hundred eighty-nine million, nine hundred sixty-four thousand, nine hundred forty-seven".