245991191 has 2 divisors, whose sum is σ = 245991192. Its totient is φ = 245991190.

The previous prime is 245991149. The next prime is 245991209. The reversal of 245991191 is 191199542.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245991191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (245991121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122995595 + 122995596.

It is an arithmetic number, because the mean of its divisors is an integer number (122995596).

Almost surely, 2^245991191 is an apocalyptic number.

245991191 is a deficient number, since it is larger than the sum of its proper divisors (1).

245991191 is an equidigital number, since it uses as much as digits as its factorization.

245991191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29160, while the sum is 41.

The square root of 245991191 is about 15684.1063181808. The cubic root of 245991191 is about 626.5751764290.

The spelling of 245991191 in words is "two hundred forty-five million, nine hundred ninety-one thousand, one hundred ninety-one".