251161189 has 2 divisors, whose sum is σ = 251161190. Its totient is φ = 251161188.

The previous prime is 251161177. The next prime is 251161193. The reversal of 251161189 is 981161152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 143209089 + 107952100 = 11967^2 + 10390^2 .

It is a cyclic number.

It is not a de Polignac number, because 251161189 - 2¹¹ = 251159141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251161159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125580594 + 125580595.

It is an arithmetic number, because the mean of its divisors is an integer number (125580595).

Almost surely, 2^251161189 is an apocalyptic number.

It is an amenable number.

251161189 is a deficient number, since it is larger than the sum of its proper divisors (1).

251161189 is an equidigital number, since it uses as much as digits as its factorization.

251161189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 34.

The square root of 251161189 is about 15848.0657810346. The cubic root of 251161189 is about 630.9343564062.

The spelling of 251161189 in words is "two hundred fifty-one million, one hundred sixty-one thousand, one hundred eighty-nine".