1256532513 has 4 divisors (see below), whose sum is σ = 1675376688. Its totient is φ = 837688340.

The previous prime is 1256532467. The next prime is 1256532521. The reversal of 1256532513 is 3152356521.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1256532513 - 2⁹ = 1256532001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1256532523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209422083 + ... + 209422088.

It is an arithmetic number, because the mean of its divisors is an integer number (418844172).

Almost surely, 2^1256532513 is an apocalyptic number.

It is an amenable number.

1256532513 is a deficient number, since it is larger than the sum of its proper divisors (418844175).

1256532513 is an equidigital number, since it uses as much as digits as its factorization.

1256532513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418844174.

The product of its digits is 27000, while the sum is 33.

The square root of 1256532513 is about 35447.6023589749. The cubic root of 1256532513 is about 1079.0906019251.

The spelling of 1256532513 in words is "one billion, two hundred fifty-six million, five hundred thirty-two thousand, five hundred thirteen".