399622819 has 2 divisors, whose sum is σ = 399622820. Its totient is φ = 399622818.

The previous prime is 399622807. The next prime is 399622849. The reversal of 399622819 is 918226993.

It is a weak prime.

It is an emirp because it is prime and its reverse (918226993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399622819 - 2⁵ = 399622787 is a prime.

It is a super-2 number, since 2×399622819² = 319396794931013522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (399622849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199811409 + 199811410.

It is an arithmetic number, because the mean of its divisors is an integer number (199811410).

Almost surely, 2^399622819 is an apocalyptic number.

399622819 is a deficient number, since it is larger than the sum of its proper divisors (1).

399622819 is an equidigital number, since it uses as much as digits as its factorization.

399622819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 419904, while the sum is 49.

The square root of 399622819 is about 19990.5682510528. The cubic root of 399622819 is about 736.5746357827.

The spelling of 399622819 in words is "three hundred ninety-nine million, six hundred twenty-two thousand, eight hundred nineteen".