188974270991 has 4 divisors (see below), whose sum is σ = 206153750184. Its totient is φ = 171794791800.

The previous prime is 188974270967. The next prime is 188974271033. The reversal of 188974270991 is 199072479881.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-188974270991 is a prime.

It is a super-2 number, since 2×188974270991² (a number of 23 digits) contains 22 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 (188974270091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8589739580 + ... + 8589739601.

It is an arithmetic number, because the mean of its divisors is an integer number (51538437546).

Almost surely, 2^188974270991 is an apocalyptic number.

188974270991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

188974270991 is a deficient number, since it is larger than the sum of its proper divisors (17179479193).

188974270991 is a wasteful number, since it uses less digits than its factorization.

188974270991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17179479192.

The product of its (nonzero) digits is 18289152, while the sum is 65.

The spelling of 188974270991 in words is "one hundred eighty-eight billion, nine hundred seventy-four million, two hundred seventy thousand, nine hundred ninety-one".