1338579257 has 4 divisors (see below), whose sum is σ = 1338653940. Its totient is φ = 1338504576.

The previous prime is 1338579233. The next prime is 1338579301. The reversal of 1338579257 is 7529758331.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1148938816 + 189640441 = 33896^2 + 13771^2 .

It is a cyclic number.

It is not a de Polignac number, because 1338579257 - 2¹⁴ = 1338562873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1338579227) 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, 7469 + ... + 52277.

It is an arithmetic number, because the mean of its divisors is an integer number (334663485).

It is a Poulet number, since it divides 2^1338579256-1.

Almost surely, 2^1338579257 is an apocalyptic number.

1338579257 is the 29873-rd pentagonal number.

It is an amenable number.

1338579257 is a deficient number, since it is larger than the sum of its proper divisors (74683).

1338579257 is an equidigital number, since it uses as much as digits as its factorization.

1338579257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74682.

The product of its digits is 1587600, while the sum is 50.

The square root of 1338579257 is about 36586.5994183663. The cubic root of 1338579257 is about 1102.0839988650.

The spelling of 1338579257 in words is "one billion, three hundred thirty-eight million, five hundred seventy-nine thousand, two hundred fifty-seven".