399651803 has 2 divisors, whose sum is σ = 399651804. Its totient is φ = 399651802.

The previous prime is 399651767. The next prime is 399651839. The reversal of 399651803 is 308156993.

It is a balanced prime because it is at equal distance from previous prime (399651767) and next prime (399651839).

It is a cyclic number.

It is not a de Polignac number, because 399651803 - 2⁶ = 399651739 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (399653803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199825901 + 199825902.

It is an arithmetic number, because the mean of its divisors is an integer number (199825902).

Almost surely, 2^399651803 is an apocalyptic number.

399651803 is a deficient number, since it is larger than the sum of its proper divisors (1).

399651803 is an equidigital number, since it uses as much as digits as its factorization.

399651803 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 174960, while the sum is 44.

The square root of 399651803 is about 19991.2931797820. The cubic root of 399651803 is about 736.5924428765.

The spelling of 399651803 in words is "three hundred ninety-nine million, six hundred fifty-one thousand, eight hundred three".