1256454509 has 2 divisors, whose sum is σ = 1256454510. Its totient is φ = 1256454508.

The previous prime is 1256454469. The next prime is 1256454523. The reversal of 1256454509 is 9054546521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 901320484 + 355134025 = 30022^2 + 18845^2 .

It is a cyclic number.

It is not a de Polignac number, because 1256454509 - 2¹² = 1256450413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1256454559) 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, 628227254 + 628227255.

It is an arithmetic number, because the mean of its divisors is an integer number (628227255).

Almost surely, 2^1256454509 is an apocalyptic number.

It is an amenable number.

1256454509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256454509 is an equidigital number, since it uses as much as digits as its factorization.

1256454509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216000, while the sum is 41.

The square root of 1256454509 is about 35446.5020700210. The cubic root of 1256454509 is about 1079.0682719219.

The spelling of 1256454509 in words is "one billion, two hundred fifty-six million, four hundred fifty-four thousand, five hundred nine".