251124421 has 2 divisors, whose sum is σ = 251124422. Its totient is φ = 251124420.

The previous prime is 251124407. The next prime is 251124437. The reversal of 251124421 is 124421152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 170824900 + 80299521 = 13070^2 + 8961^2 .

It is a cyclic number.

It is not a de Polignac number, because 251124421 - 2⁹ = 251123909 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 251124392 and 251124401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251124721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125562210 + 125562211.

It is an arithmetic number, because the mean of its divisors is an integer number (125562211).

Almost surely, 2^251124421 is an apocalyptic number.

It is an amenable number.

251124421 is a deficient number, since it is larger than the sum of its proper divisors (1).

251124421 is an equidigital number, since it uses as much as digits as its factorization.

251124421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 640, while the sum is 22.

The square root of 251124421 is about 15846.9057232003. The cubic root of 251124421 is about 630.9035669803.

Adding to 251124421 its reverse (124421152), we get a palindrome (375545573).

The spelling of 251124421 in words is "two hundred fifty-one million, one hundred twenty-four thousand, four hundred twenty-one".