1256342407 has 2 divisors, whose sum is σ = 1256342408. Its totient is φ = 1256342406.

The previous prime is 1256342389. The next prime is 1256342411. The reversal of 1256342407 is 7042436521.

It is a strong prime.

It is an emirp because it is prime and its reverse (7042436521) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1256342407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1256342107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628171203 + 628171204.

It is an arithmetic number, because the mean of its divisors is an integer number (628171204).

Almost surely, 2^1256342407 is an apocalyptic number.

1256342407 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256342407 is an equidigital number, since it uses as much as digits as its factorization.

1256342407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 34.

The square root of 1256342407 is about 35444.9207503699. The cubic root of 1256342407 is about 1079.0361791539.

Adding to 1256342407 its reverse (7042436521), we get a palindrome (8298778928).

The spelling of 1256342407 in words is "one billion, two hundred fifty-six million, three hundred forty-two thousand, four hundred seven".