251172461 has 2 divisors, whose sum is σ = 251172462. Its totient is φ = 251172460.

The previous prime is 251172431. The next prime is 251172463. The reversal of 251172461 is 164271152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204318436 + 46854025 = 14294^2 + 6845^2 .

It is a cyclic number.

It is not a de Polignac number, because 251172461 - 2²⁶ = 184063597 is a prime.

Together with 251172463, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251172463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125586230 + 125586231.

It is an arithmetic number, because the mean of its divisors is an integer number (125586231).

Almost surely, 2^251172461 is an apocalyptic number.

It is an amenable number.

251172461 is a deficient number, since it is larger than the sum of its proper divisors (1).

251172461 is an equidigital number, since it uses as much as digits as its factorization.

251172461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 29.

The square root of 251172461 is about 15848.4214040390. The cubic root of 251172461 is about 630.9437949474.

The spelling of 251172461 in words is "two hundred fifty-one million, one hundred seventy-two thousand, four hundred sixty-one".