1315551779 has 2 divisors, whose sum is σ = 1315551780. Its totient is φ = 1315551778.

The previous prime is 1315551719. The next prime is 1315551781. The reversal of 1315551779 is 9771555131.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1315551779 - 2²⁴ = 1298774563 is a prime.

Together with 1315551781, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1315551719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 657775889 + 657775890.

It is an arithmetic number, because the mean of its divisors is an integer number (657775890).

Almost surely, 2^1315551779 is an apocalyptic number.

1315551779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1315551779 is an equidigital number, since it uses as much as digits as its factorization.

1315551779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165375, while the sum is 44.

The square root of 1315551779 is about 36270.5359624034. The cubic root of 1315551779 is about 1095.7277201491.

The spelling of 1315551779 in words is "one billion, three hundred fifteen million, five hundred fifty-one thousand, seven hundred seventy-nine".