399766711397 has 2 divisors, whose sum is σ = 399766711398. Its totient is φ = 399766711396.

The previous prime is 399766711369. The next prime is 399766711403. The reversal of 399766711397 is 793117667993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 361211818081 + 38554893316 = 601009^2 + 196354^2 .

It is a cyclic number.

It is not a de Polignac number, because 399766711397 - 2¹⁸ = 399766449253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399766710397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199883355698 + 199883355699.

It is an arithmetic number, because the mean of its divisors is an integer number (199883355699).

Almost surely, 2^399766711397 is an apocalyptic number.

It is an amenable number.

399766711397 is a deficient number, since it is larger than the sum of its proper divisors (1).

399766711397 is an equidigital number, since it uses as much as digits as its factorization.

399766711397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81015228, while the sum is 68.

The spelling of 399766711397 in words is "three hundred ninety-nine billion, seven hundred sixty-six million, seven hundred eleven thousand, three hundred ninety-seven".