399099401 has 2 divisors, whose sum is σ = 399099402. Its totient is φ = 399099400.

The previous prime is 399099397. The next prime is 399099403. The reversal of 399099401 is 104990993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 350588176 + 48511225 = 18724^2 + 6965^2 .

It is a cyclic number.

It is not a de Polignac number, because 399099401 - 2² = 399099397 is a prime.

It is a Sophie Germain prime.

Together with 399099403, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (399099403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199549700 + 199549701.

It is an arithmetic number, because the mean of its divisors is an integer number (199549701).

Almost surely, 2^399099401 is an apocalyptic number.

It is an amenable number.

399099401 is a deficient number, since it is larger than the sum of its proper divisors (1).

399099401 is an equidigital number, since it uses as much as digits as its factorization.

399099401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 78732, while the sum is 44.

The square root of 399099401 is about 19977.4723376107. The cubic root of 399099401 is about 736.2529116888.

The spelling of 399099401 in words is "three hundred ninety-nine million, ninety-nine thousand, four hundred one".