191969 has 2 divisors, whose sum is σ = 191970. Its totient is φ = 191968.

The previous prime is 191953. The next prime is 191977. The reversal of 191969 is 969191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113569 + 78400 = 337^2 + 280^2 .

It is a cyclic number.

It is not a de Polignac number, because 191969 - 2⁴ = 191953 is a prime.

It is a super-2 number, since 2×191969² = 73704193922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (191929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95984 + 95985.

It is an arithmetic number, because the mean of its divisors is an integer number (95985).

2¹⁹¹⁹⁶⁹ is an apocalyptic number.

It is an amenable number.

191969 is a deficient number, since it is larger than the sum of its proper divisors (1).

191969 is an equidigital number, since it uses as much as digits as its factorization.

191969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4374, while the sum is 35.

The square root of 191969 is about 438.1426708277. The cubic root of 191969 is about 57.6868778024.

The spelling of 191969 in words is "one hundred ninety-one thousand, nine hundred sixty-nine".