1318686253 has 4 divisors (see below), whose sum is σ = 1354326460. Its totient is φ = 1283046048.

The previous prime is 1318686247. The next prime is 1318686287. The reversal of 1318686253 is 3526868131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3526868131 = 137 ⋅25743563.

It can be written as a sum of positive squares in 2 ways, for example, as 654438724 + 664247529 = 25582^2 + 25773^2 .

It is a cyclic number.

It is not a de Polignac number, because 1318686253 - 2⁹ = 1318685741 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 (1318686223) 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, 17820048 + ... + 17820121.

It is an arithmetic number, because the mean of its divisors is an integer number (338581615).

Almost surely, 2^1318686253 is an apocalyptic number.

It is an amenable number.

1318686253 is a deficient number, since it is larger than the sum of its proper divisors (35640207).

1318686253 is an equidigital number, since it uses as much as digits as its factorization.

1318686253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35640206.

The product of its digits is 207360, while the sum is 43.

The square root of 1318686253 is about 36313.7199003352. The cubic root of 1318686253 is about 1096.5972680632.

The spelling of 1318686253 in words is "one billion, three hundred eighteen million, six hundred eighty-six thousand, two hundred fifty-three".