1338918731 has 2 divisors, whose sum is σ = 1338918732. Its totient is φ = 1338918730.

The previous prime is 1338918677. The next prime is 1338918739. The reversal of 1338918731 is 1378198331.

It is a strong prime.

It is an emirp because it is prime and its reverse (1378198331) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1338918731 - 2²² = 1334724427 is a prime.

It is a super-2 number, since 2×1338918731² = 3585406736445300722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1338918739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 669459365 + 669459366.

It is an arithmetic number, because the mean of its divisors is an integer number (669459366).

Almost surely, 2^1338918731 is an apocalyptic number.

1338918731 is a deficient number, since it is larger than the sum of its proper divisors (1).

1338918731 is an equidigital number, since it uses as much as digits as its factorization.

1338918731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 44.

The square root of 1338918731 is about 36591.2384458356. The cubic root of 1338918731 is about 1102.1771566512.

The spelling of 1338918731 in words is "one billion, three hundred thirty-eight million, nine hundred eighteen thousand, seven hundred thirty-one".