394790857 has 2 divisors, whose sum is σ = 394790858. Its totient is φ = 394790856.

The previous prime is 394790831. The next prime is 394790861. The reversal of 394790857 is 758097493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 283720336 + 111070521 = 16844^2 + 10539^2 .

It is a cyclic number.

It is not a de Polignac number, because 394790857 - 2¹¹ = 394788809 is a prime.

It is not a weakly prime, because it can be changed into another prime (394790897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197395428 + 197395429.

It is an arithmetic number, because the mean of its divisors is an integer number (197395429).

Almost surely, 2^394790857 is an apocalyptic number.

It is an amenable number.

394790857 is a deficient number, since it is larger than the sum of its proper divisors (1).

394790857 is an equidigital number, since it uses as much as digits as its factorization.

394790857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1905120, while the sum is 52.

The square root of 394790857 is about 19869.3446545174. The cubic root of 394790857 is about 733.5938729660.

The spelling of 394790857 in words is "three hundred ninety-four million, seven hundred ninety thousand, eight hundred fifty-seven".