191338491 has 16 divisors (see below), whose sum is σ = 266349600. Its totient is φ = 122024448.

The previous prime is 191338481. The next prime is 191338501. The reversal of 191338491 is 194833191.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (191338481) and next prime (191338501).

It is not a de Polignac number, because 191338491 - 2¹⁴ = 191322107 is a prime.

It is a super-2 number, since 2×191338491² = 73220836276314162, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (191338421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 606 + ... + 19571.

It is an arithmetic number, because the mean of its divisors is an integer number (16646850).

Almost surely, 2^191338491 is an apocalyptic number.

191338491 is a deficient number, since it is larger than the sum of its proper divisors (75011109).

191338491 is a wasteful number, since it uses less digits than its factorization.

191338491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20318.

The product of its digits is 23328, while the sum is 39.

The square root of 191338491 is about 13832.5157147932. The cubic root of 191338491 is about 576.2365233539.

It can be divided in two parts, 1913 and 38491, that added together give a palindrome (40404).

The spelling of 191338491 in words is "one hundred ninety-one million, three hundred thirty-eight thousand, four hundred ninety-one".