1368636557 has 12 divisors (see below), whose sum is σ = 1458801756. Its totient is φ = 1283731200.

The previous prime is 1368636491. The next prime is 1368636583. The reversal of 1368636557 is 7556368631.

It can be written as a sum of positive squares in 2 ways, for example, as 1017673801 + 350962756 = 31901^2 + 18734^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1368636557 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 (1368635557) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17693 + ... + 55229.

It is an arithmetic number, because the mean of its divisors is an integer number (121566813).

Almost surely, 2^1368636557 is an apocalyptic number.

It is an amenable number.

1368636557 is a deficient number, since it is larger than the sum of its proper divisors (90165199).

1368636557 is a wasteful number, since it uses less digits than its factorization.

1368636557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37676 (or 37657 counting only the distinct ones).

The product of its digits is 2721600, while the sum is 50.

The square root of 1368636557 is about 36995.0882820950. The cubic root of 1368636557 is about 1110.2719775597.

The spelling of 1368636557 in words is "one billion, three hundred sixty-eight million, six hundred thirty-six thousand, five hundred fifty-seven".