191251 has 2 divisors, whose sum is σ = 191252. Its totient is φ = 191250.

The previous prime is 191249. The next prime is 191281. The reversal of 191251 is 152191.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 191251 - 2¹ = 191249 is a prime.

Together with 191249, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (191231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95625 + 95626.

It is an arithmetic number, because the mean of its divisors is an integer number (95626).

2¹⁹¹²⁵¹ is an apocalyptic number.

191251 is a deficient number, since it is larger than the sum of its proper divisors (1).

191251 is an equidigital number, since it uses as much as digits as its factorization.

191251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90, while the sum is 19.

The square root of 191251 is about 437.3225354358. The cubic root of 191251 is about 57.6148680433.

Subtracting from 191251 its reverse (152191), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 191251 in words is "one hundred ninety-one thousand, two hundred fifty-one".