189991563 has 8 divisors (see below), whose sum is σ = 253992000. Its totient is φ = 126326088.

The previous prime is 189991553. The next prime is 189991567. The reversal of 189991563 is 365199981.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 189991563 - 2¹³ = 189983371 is a prime.

It is a super-2 number, since 2×189991563² = 72193588022365938, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (189991567) 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 7 ways as a sum of consecutive naturals, for example, 82413 + ... + 84686.

It is an arithmetic number, because the mean of its divisors is an integer number (31749000).

Almost surely, 2^189991563 is an apocalyptic number.

189991563 is a deficient number, since it is larger than the sum of its proper divisors (64000437).

189991563 is a wasteful number, since it uses less digits than its factorization.

189991563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167481.

The product of its digits is 524880, while the sum is 51.

The square root of 189991563 is about 13783.7427065366. The cubic root of 189991563 is about 574.8811983923.

The spelling of 189991563 in words is "one hundred eighty-nine million, nine hundred ninety-one thousand, five hundred sixty-three".