399550889 has 2 divisors, whose sum is σ = 399550890. Its totient is φ = 399550888.

The previous prime is 399550843. The next prime is 399550897. The reversal of 399550889 is 988055993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 312688489 + 86862400 = 17683^2 + 9320^2 .

It is a cyclic number.

It is not a de Polignac number, because 399550889 - 2¹² = 399546793 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (399550819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199775444 + 199775445.

It is an arithmetic number, because the mean of its divisors is an integer number (199775445).

Almost surely, 2^399550889 is an apocalyptic number.

It is an amenable number.

399550889 is a deficient number, since it is larger than the sum of its proper divisors (1).

399550889 is an equidigital number, since it uses as much as digits as its factorization.

399550889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3499200, while the sum is 56.

The square root of 399550889 is about 19988.7690716562. The cubic root of 399550889 is about 736.5304399475.

The spelling of 399550889 in words is "three hundred ninety-nine million, five hundred fifty thousand, eight hundred eighty-nine".