251522231 has 2 divisors, whose sum is σ = 251522232. Its totient is φ = 251522230.

The previous prime is 251522197. The next prime is 251522233. The reversal of 251522231 is 132225152.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251522231 is a prime.

It is a super-2 number, since 2×251522231² = 126526865374434722, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 251522233, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 251522197 and 251522206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251522233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125761115 + 125761116.

It is an arithmetic number, because the mean of its divisors is an integer number (125761116).

Almost surely, 2^251522231 is an apocalyptic number.

251522231 is a deficient number, since it is larger than the sum of its proper divisors (1).

251522231 is an equidigital number, since it uses as much as digits as its factorization.

251522231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1200, while the sum is 23.

The square root of 251522231 is about 15859.4524180376. The cubic root of 251522231 is about 631.2365325232.

Adding to 251522231 its reverse (132225152), we get a palindrome (383747383).

The spelling of 251522231 in words is "two hundred fifty-one million, five hundred twenty-two thousand, two hundred thirty-one".