1256134423 has 4 divisors (see below), whose sum is σ = 1290084040. Its totient is φ = 1222184808.

The previous prime is 1256134393. The next prime is 1256134457. The reversal of 1256134423 is 3244316521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3244316521 = 7901 ⋅410621.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1256134423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256134223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16974753 + ... + 16974826.

It is an arithmetic number, because the mean of its divisors is an integer number (322521010).

Almost surely, 2^1256134423 is an apocalyptic number.

1256134423 is a deficient number, since it is larger than the sum of its proper divisors (33949617).

1256134423 is an equidigital number, since it uses as much as digits as its factorization.

1256134423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33949616.

The product of its digits is 17280, while the sum is 31.

The square root of 1256134423 is about 35441.9867247873. The cubic root of 1256134423 is about 1078.9766320525.

The spelling of 1256134423 in words is "one billion, two hundred fifty-six million, one hundred thirty-four thousand, four hundred twenty-three".