1312551538 has 16 divisors (see below), whose sum is σ = 2086419384. Its totient is φ = 617144320.

The previous prime is 1312551529. The next prime is 1312551547. The reversal of 1312551538 is 8351552131.

It is an interprime number because it is at equal distance from previous prime (1312551529) and next prime (1312551547).

It can be written as a sum of positive squares in 4 ways, for example, as 846984609 + 465566929 = 29103^2 + 21577^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25518 + ... + 57238.

Almost surely, 2^1312551538 is an apocalyptic number.

1312551538 is a deficient number, since it is larger than the sum of its proper divisors (773867846).

1312551538 is a wasteful number, since it uses less digits than its factorization.

1312551538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32957.

The product of its digits is 18000, while the sum is 34.

The square root of 1312551538 is about 36229.1531504671. The cubic root of 1312551538 is about 1094.8941156833.

The spelling of 1312551538 in words is "one billion, three hundred twelve million, five hundred fifty-one thousand, five hundred thirty-eight".