1313126257 has 4 divisors (see below), whose sum is σ = 1390368996. Its totient is φ = 1235883520.

The previous prime is 1313126249. The next prime is 1313126261. The reversal of 1313126257 is 7526213131.

It is a happy number.

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 1042062961 + 271063296 = 32281^2 + 16464^2 .

It is a cyclic number.

It is not a de Polignac number, because 1313126257 - 2³ = 1313126249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1313126657) 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, 38621344 + ... + 38621377.

It is an arithmetic number, because the mean of its divisors is an integer number (347592249).

Almost surely, 2^1313126257 is an apocalyptic number.

1313126257 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1313126257 is a deficient number, since it is larger than the sum of its proper divisors (77242739).

1313126257 is an equidigital number, since it uses as much as digits as its factorization.

1313126257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77242738.

The product of its digits is 7560, while the sum is 31.

The square root of 1313126257 is about 36237.0840024415. The cubic root of 1313126257 is about 1095.0538972519.

Adding to 1313126257 its reverse (7526213131), we get a palindrome (8839339388).

The spelling of 1313126257 in words is "one billion, three hundred thirteen million, one hundred twenty-six thousand, two hundred fifty-seven".