251191 has 2 divisors, whose sum is σ = 251192. Its totient is φ = 251190.

The previous prime is 251179. The next prime is 251197. The reversal of 251191 is 191152.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 251191 - 2⁵ = 251159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125595 + 125596.

It is an arithmetic number, because the mean of its divisors is an integer number (125596).

2²⁵¹¹⁹¹ is an apocalyptic number.

251191 is a deficient number, since it is larger than the sum of its proper divisors (1).

251191 is an equidigital number, since it uses as much as digits as its factorization.

251191 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 251191 is about 501.1895848878. The cubic root of 251191 is about 63.0959317853.

The spelling of 251191 in words is "two hundred fifty-one thousand, one hundred ninety-one".