1366257397 has 2 divisors, whose sum is σ = 1366257398. Its totient is φ = 1366257396.

The previous prime is 1366257379. The next prime is 1366257469. The reversal of 1366257397 is 7937526631.

Together with previous prime (1366257379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 757845841 + 608411556 = 27529^2 + 24666^2 .

It is an emirp because it is prime and its reverse (7937526631) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1366257397 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1366257397.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1366257337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 683128698 + 683128699.

It is an arithmetic number, because the mean of its divisors is an integer number (683128699).

Almost surely, 2^1366257397 is an apocalyptic number.

It is an amenable number.

1366257397 is a deficient number, since it is larger than the sum of its proper divisors (1).

1366257397 is an equidigital number, since it uses as much as digits as its factorization.

1366257397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1428840, while the sum is 49.

The square root of 1366257397 is about 36962.9192164255. The cubic root of 1366257397 is about 1109.6282598480.

The spelling of 1366257397 in words is "one billion, three hundred sixty-six million, two hundred fifty-seven thousand, three hundred ninety-seven".