191940901 has 2 divisors, whose sum is σ = 191940902. Its totient is φ = 191940900.

The previous prime is 191940893. The next prime is 191940919. The reversal of 191940901 is 109049191.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 99800100 + 92140801 = 9990^2 + 9599^2 .

It is a cyclic number.

It is not a de Polignac number, because 191940901 - 2³ = 191940893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191940101) 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 as a sum of consecutive naturals, namely, 95970450 + 95970451.

It is an arithmetic number, because the mean of its divisors is an integer number (95970451).

Almost surely, 2^191940901 is an apocalyptic number.

It is an amenable number.

191940901 is a deficient number, since it is larger than the sum of its proper divisors (1).

191940901 is an equidigital number, since it uses as much as digits as its factorization.

191940901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 34.

The square root of 191940901 is about 13854.2737449496. The cubic root of 191940901 is about 576.8406307242.

The spelling of 191940901 in words is "one hundred ninety-one million, nine hundred forty thousand, nine hundred one".