251198191 has 2 divisors, whose sum is σ = 251198192. Its totient is φ = 251198190.

The previous prime is 251198179. The next prime is 251198197. The reversal of 251198191 is 191891152.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 251198191 - 2⁹ = 251197679 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 251198191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251198197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125599095 + 125599096.

It is an arithmetic number, because the mean of its divisors is an integer number (125599096).

Almost surely, 2^251198191 is an apocalyptic number.

251198191 is a deficient number, since it is larger than the sum of its proper divisors (1).

251198191 is an equidigital number, since it uses as much as digits as its factorization.

251198191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 37.

The square root of 251198191 is about 15849.2331360227. The cubic root of 251198191 is about 630.9653387497.

The spelling of 251198191 in words is "two hundred fifty-one million, one hundred ninety-eight thousand, one hundred ninety-one".