1256311447 has 4 divisors (see below), whose sum is σ = 1256431176. Its totient is φ = 1256191720.

The previous prime is 1256311421. The next prime is 1256311453. The reversal of 1256311447 is 7441136521.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1256311447 - 2⁷ = 1256311319 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 (1256311247) 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, 42433 + ... + 65674.

It is an arithmetic number, because the mean of its divisors is an integer number (314107794).

Almost surely, 2^1256311447 is an apocalyptic number.

1256311447 is a deficient number, since it is larger than the sum of its proper divisors (119729).

1256311447 is a wasteful number, since it uses less digits than its factorization.

1256311447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119728.

The product of its digits is 20160, while the sum is 34.

The square root of 1256311447 is about 35444.4840137362. The cubic root of 1256311447 is about 1079.0273155314.

Adding to 1256311447 its reverse (7441136521), we get a palindrome (8697447968).

The spelling of 1256311447 in words is "one billion, two hundred fifty-six million, three hundred eleven thousand, four hundred forty-seven".