399226837 has 2 divisors, whose sum is σ = 399226838. Its totient is φ = 399226836.

The previous prime is 399226831. The next prime is 399226859. The reversal of 399226837 is 738622993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 321628356 + 77598481 = 17934^2 + 8809^2 .

It is a cyclic number.

It is not a de Polignac number, because 399226837 - 2³ = 399226829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399226831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199613418 + 199613419.

It is an arithmetic number, because the mean of its divisors is an integer number (199613419).

Almost surely, 2^399226837 is an apocalyptic number.

It is an amenable number.

399226837 is a deficient number, since it is larger than the sum of its proper divisors (1).

399226837 is an equidigital number, since it uses as much as digits as its factorization.

399226837 is an evil number, because the sum of its binary digits is even.

The product of its digits is 979776, while the sum is 49.

The square root of 399226837 is about 19980.6615756336. The cubic root of 399226837 is about 736.3312673910.

The spelling of 399226837 in words is "three hundred ninety-nine million, two hundred twenty-six thousand, eight hundred thirty-seven".