1356123557 has 2 divisors, whose sum is σ = 1356123558. Its totient is φ = 1356123556.

The previous prime is 1356123553. The next prime is 1356123563. The reversal of 1356123557 is 7553216531.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1163219236 + 192904321 = 34106^2 + 13889^2 .

It is a cyclic number.

It is not a de Polignac number, because 1356123557 - 2² = 1356123553 is a prime.

It is a super-2 number, since 2×1356123557² = 3678142203700664498, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1356123557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1356123553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 678061778 + 678061779.

It is an arithmetic number, because the mean of its divisors is an integer number (678061779).

Almost surely, 2^1356123557 is an apocalyptic number.

It is an amenable number.

1356123557 is a deficient number, since it is larger than the sum of its proper divisors (1).

1356123557 is an equidigital number, since it uses as much as digits as its factorization.

1356123557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94500, while the sum is 38.

The square root of 1356123557 is about 36825.5829145989. The cubic root of 1356123557 is about 1106.8779942610.

The spelling of 1356123557 in words is "one billion, three hundred fifty-six million, one hundred twenty-three thousand, five hundred fifty-seven".