251253461 has 2 divisors, whose sum is σ = 251253462. Its totient is φ = 251253460.

The previous prime is 251253439. The next prime is 251253463. The reversal of 251253461 is 164352152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 248661361 + 2592100 = 15769^2 + 1610^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251253461 is a prime.

It is a Sophie Germain prime.

Together with 251253463, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251253463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125626730 + 125626731.

It is an arithmetic number, because the mean of its divisors is an integer number (125626731).

Almost surely, 2^251253461 is an apocalyptic number.

It is an amenable number.

251253461 is a deficient number, since it is larger than the sum of its proper divisors (1).

251253461 is an equidigital number, since it uses as much as digits as its factorization.

251253461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 29.

The square root of 251253461 is about 15850.9766576069. The cubic root of 251253461 is about 631.0116115045.

The spelling of 251253461 in words is "two hundred fifty-one million, two hundred fifty-three thousand, four hundred sixty-one".