399464993 has 2 divisors, whose sum is σ = 399464994. Its totient is φ = 399464992.

The previous prime is 399464959. The next prime is 399465007.

399464993 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 338265664 + 61199329 = 18392^2 + 7823^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 399464993 - 2¹⁰ = 399463969 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (399464953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199732496 + 199732497.

It is an arithmetic number, because the mean of its divisors is an integer number (199732497).

Almost surely, 2^399464993 is an apocalyptic number.

It is an amenable number.

399464993 is a deficient number, since it is larger than the sum of its proper divisors (1).

399464993 is an equidigital number, since it uses as much as digits as its factorization.

399464993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5668704, while the sum is 56.

The square root of 399464993 is about 19986.6203496239. The cubic root of 399464993 is about 736.4776560556.

It can be divided in two parts, 39946 and 4993, that multiplied together give a triangular number (199450378 = T₁₉₉₇₂).

The spelling of 399464993 in words is "three hundred ninety-nine million, four hundred sixty-four thousand, nine hundred ninety-three".