399786461861 has 2 divisors, whose sum is σ = 399786461862. Its totient is φ = 399786461860.

The previous prime is 399786461857. The next prime is 399786461881. The reversal of 399786461861 is 168164687993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 271331601025 + 128454860836 = 520895^2 + 358406^2 .

It is an emirp because it is prime and its reverse (168164687993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399786461861 - 2² = 399786461857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 399786461791 and 399786461800.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399786461821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199893230930 + 199893230931.

It is an arithmetic number, because the mean of its divisors is an integer number (199893230931).

Almost surely, 2^399786461861 is an apocalyptic number.

It is an amenable number.

399786461861 is a deficient number, since it is larger than the sum of its proper divisors (1).

399786461861 is an equidigital number, since it uses as much as digits as its factorization.

399786461861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94058496, while the sum is 68.

The spelling of 399786461861 in words is "three hundred ninety-nine billion, seven hundred eighty-six million, four hundred sixty-one thousand, eight hundred sixty-one".