1256831447 has 4 divisors (see below), whose sum is σ = 1256914296. Its totient is φ = 1256748600.

The previous prime is 1256831431. The next prime is 1256831449. The reversal of 1256831447 is 7441386521.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1256831447 - 2⁴ = 1256831431 is a prime.

It is a super-2 number, since 2×1256831447² = 3159250572336227618, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256831449) 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 in 3 ways as a sum of consecutive naturals, for example, 11429 + ... + 51422.

It is an arithmetic number, because the mean of its divisors is an integer number (314228574).

Almost surely, 2^1256831447 is an apocalyptic number.

1256831447 is a deficient number, since it is larger than the sum of its proper divisors (82849).

1256831447 is an equidigital number, since it uses as much as digits as its factorization.

1256831447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82848.

The product of its digits is 161280, while the sum is 41.

The square root of 1256831447 is about 35451.8186698511. The cubic root of 1256831447 is about 1079.1761684317.

The spelling of 1256831447 in words is "one billion, two hundred fifty-six million, eight hundred thirty-one thousand, four hundred forty-seven".