1555393139 has 2 divisors, whose sum is σ = 1555393140. Its totient is φ = 1555393138.

The previous prime is 1555393123. The next prime is 1555393153. The reversal of 1555393139 is 9313935551.

It is a strong prime.

It is an emirp because it is prime and its reverse (9313935551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1555393139 - 2⁴ = 1555393123 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1555393139.

It is not a weakly prime, because it can be changed into another prime (1555395139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 777696569 + 777696570.

It is an arithmetic number, because the mean of its divisors is an integer number (777696570).

Almost surely, 2^1555393139 is an apocalyptic number.

1555393139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1555393139 is an equidigital number, since it uses as much as digits as its factorization.

1555393139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 273375, while the sum is 44.

The square root of 1555393139 is about 39438.4728279379. The cubic root of 1555393139 is about 1158.6352208723.

The spelling of 1555393139 in words is "one billion, five hundred fifty-five million, three hundred ninety-three thousand, one hundred thirty-nine".