1256931938749 has 4 divisors (see below), whose sum is σ = 1257526797436. Its totient is φ = 1256337080064.

The previous prime is 1256931938737. The next prime is 1256931938777. The reversal of 1256931938749 is 9478391396521.

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

It can be written as a sum of positive squares in 2 ways, for example, as 106070719225 + 1150861219524 = 325685^2 + 1072782^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1256931938749 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 (1256931938719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 297426174 + ... + 297430399.

It is an arithmetic number, because the mean of its divisors is an integer number (314381699359).

Almost surely, 2^{1256931938749} is an apocalyptic number.

It is an amenable number.

1256931938749 is a deficient number, since it is larger than the sum of its proper divisors (594858687).

1256931938749 is an equidigital number, since it uses as much as digits as its factorization.

1256931938749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594858686.

The product of its digits is 88179840, while the sum is 67.

The spelling of 1256931938749 in words is "one trillion, two hundred fifty-six billion, nine hundred thirty-one million, nine hundred thirty-eight thousand, seven hundred forty-nine".