399394026893441 has 2 divisors, whose sum is σ = 399394026893442. Its totient is φ = 399394026893440.

The previous prime is 399394026893371. The next prime is 399394026893453. The reversal of 399394026893441 is 144398620493993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 295881797476225 + 103512229417216 = 17201215^2 + 10174096^2 .

It is a cyclic number.

It is not a de Polignac number, because 399394026893441 - 2¹⁸ = 399394026631297 is a prime.

It is not a weakly prime, because it can be changed into another prime (399394026893341) 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, 199697013446720 + 199697013446721.

It is an arithmetic number, because the mean of its divisors is an integer number (199697013446721).

Almost surely, 2^{399394026893441} is an apocalyptic number.

It is an amenable number.

399394026893441 is a deficient number, since it is larger than the sum of its proper divisors (1).

399394026893441 is an equidigital number, since it uses as much as digits as its factorization.

399394026893441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088391168, while the sum is 74.

The spelling of 399394026893441 in words is "three hundred ninety-nine trillion, three hundred ninety-four billion, twenty-six million, eight hundred ninety-three thousand, four hundred forty-one".