1397297555681 has 2 divisors, whose sum is σ = 1397297555682. Its totient is φ = 1397297555680.

The previous prime is 1397297555653. The next prime is 1397297555683. The reversal of 1397297555681 is 1865557927931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1276222090000 + 121075465681 = 1129700^2 + 347959^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1397297555681 is a prime.

It is a super-2 number, since 2×1397297555681² (a number of 25 digits) contains 22 as substring.

Together with 1397297555683, 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 (1397297555683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 698648777840 + 698648777841.

It is an arithmetic number, because the mean of its divisors is an integer number (698648777841).

Almost surely, 2^{1397297555681} is an apocalyptic number.

It is an amenable number.

1397297555681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1397297555681 is an equidigital number, since it uses as much as digits as its factorization.

1397297555681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 142884000, while the sum is 68.

The spelling of 1397297555681 in words is "one trillion, three hundred ninety-seven billion, two hundred ninety-seven million, five hundred fifty-five thousand, six hundred eighty-one".