399662841889 has 2 divisors, whose sum is σ = 399662841890. Its totient is φ = 399662841888.

The previous prime is 399662841833. The next prime is 399662841899. The reversal of 399662841889 is 988148266993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 350691364864 + 48971477025 = 592192^2 + 221295^2 .

It is an emirp because it is prime and its reverse (988148266993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399662841889 - 2⁹ = 399662841377 is a prime.

It is not a weakly prime, because it can be changed into another prime (399662841899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199831420944 + 199831420945.

It is an arithmetic number, because the mean of its divisors is an integer number (199831420945).

Almost surely, 2^399662841889 is an apocalyptic number.

It is an amenable number.

399662841889 is a deficient number, since it is larger than the sum of its proper divisors (1).

399662841889 is an equidigital number, since it uses as much as digits as its factorization.

399662841889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 322486272, while the sum is 73.

The spelling of 399662841889 in words is "three hundred ninety-nine billion, six hundred sixty-two million, eight hundred forty-one thousand, eight hundred eighty-nine".