251578049 has 2 divisors, whose sum is σ = 251578050. Its totient is φ = 251578048.

The previous prime is 251578039. The next prime is 251578073. The reversal of 251578049 is 940875152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187690000 + 63888049 = 13700^2 + 7993^2 .

It is a cyclic number.

It is not a de Polignac number, because 251578049 - 2²⁴ = 234800833 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 251577997 and 251578015.

It is not a weakly prime, because it can be changed into another prime (251578039) 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, 125789024 + 125789025.

It is an arithmetic number, because the mean of its divisors is an integer number (125789025).

Almost surely, 2^251578049 is an apocalyptic number.

It is an amenable number.

251578049 is a deficient number, since it is larger than the sum of its proper divisors (1).

251578049 is an equidigital number, since it uses as much as digits as its factorization.

251578049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100800, while the sum is 41.

The square root of 251578049 is about 15861.2120911360. The cubic root of 251578049 is about 631.2832238959.

The spelling of 251578049 in words is "two hundred fifty-one million, five hundred seventy-eight thousand, forty-nine".