191618131 has 2 divisors, whose sum is σ = 191618132. Its totient is φ = 191618130.

The previous prime is 191618113. The next prime is 191618149. The reversal of 191618131 is 131816191.

Together with previous prime (191618113) it forms an Ormiston pair, because they use the same digits, order apart.

It is a balanced prime because it is at equal distance from previous prime (191618113) and next prime (191618149).

It is a cyclic number.

It is not a de Polignac number, because 191618131 - 2¹⁹ = 191093843 is a prime.

It is a super-2 number, since 2×191618131² = 73435016255866322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 191618093 and 191618102.

It is not a weakly prime, because it can be changed into another prime (191618731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95809065 + 95809066.

It is an arithmetic number, because the mean of its divisors is an integer number (95809066).

Almost surely, 2^191618131 is an apocalyptic number.

191618131 is a deficient number, since it is larger than the sum of its proper divisors (1).

191618131 is an equidigital number, since it uses as much as digits as its factorization.

191618131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 31.

The square root of 191618131 is about 13842.6200915867. The cubic root of 191618131 is about 576.5171087240.

The spelling of 191618131 in words is "one hundred ninety-one million, six hundred eighteen thousand, one hundred thirty-one".