399451469 has 2 divisors, whose sum is σ = 399451470. Its totient is φ = 399451468.

The previous prime is 399451463. The next prime is 399451471. The reversal of 399451469 is 964154993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209149444 + 190302025 = 14462^2 + 13795^2 .

It is a cyclic number.

It is not a de Polignac number, because 399451469 - 2⁴ = 399451453 is a prime.

It is a super-2 number, since 2×399451469² = 319122952172515922, which contains 22 as substring.

Together with 399451471, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399451463) 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, 199725734 + 199725735.

It is an arithmetic number, because the mean of its divisors is an integer number (199725735).

Almost surely, 2^399451469 is an apocalyptic number.

It is an amenable number.

399451469 is a deficient number, since it is larger than the sum of its proper divisors (1).

399451469 is an equidigital number, since it uses as much as digits as its factorization.

399451469 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1049760, while the sum is 50.

The square root of 399451469 is about 19986.2820204259. The cubic root of 399451469 is about 736.4693447422.

It can be divided in two parts, 39945 and 1469, that added together give a palindrome (41414).

The spelling of 399451469 in words is "three hundred ninety-nine million, four hundred fifty-one thousand, four hundred sixty-nine".