191887231 has 2 divisors, whose sum is σ = 191887232. Its totient is φ = 191887230.

The previous prime is 191887207. The next prime is 191887237. The reversal of 191887231 is 132788191.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 191887231 - 2¹⁵ = 191854463 is a prime.

It is a super-2 number, since 2×191887231² = 73641418841694722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191887237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95943615 + 95943616.

It is an arithmetic number, because the mean of its divisors is an integer number (95943616).

Almost surely, 2^191887231 is an apocalyptic number.

191887231 is a deficient number, since it is larger than the sum of its proper divisors (1).

191887231 is an equidigital number, since it uses as much as digits as its factorization.

191887231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 40.

The square root of 191887231 is about 13852.3366620942. The cubic root of 191887231 is about 576.7868608355.

The spelling of 191887231 in words is "one hundred ninety-one million, eight hundred eighty-seven thousand, two hundred thirty-one".