394822032821 has 2 divisors, whose sum is σ = 394822032822. Its totient is φ = 394822032820.

The previous prime is 394822032767. The next prime is 394822032833. The reversal of 394822032821 is 128230228493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 386279652196 + 8542380625 = 621514^2 + 92425^2 .

It is a cyclic number.

It is not a de Polignac number, because 394822032821 - 2¹⁰ = 394822031797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (394822032881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197411016410 + 197411016411.

It is an arithmetic number, because the mean of its divisors is an integer number (197411016411).

Almost surely, 2^394822032821 is an apocalyptic number.

It is an amenable number.

394822032821 is a deficient number, since it is larger than the sum of its proper divisors (1).

394822032821 is an equidigital number, since it uses as much as digits as its factorization.

394822032821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 331776, while the sum is 44.

The spelling of 394822032821 in words is "three hundred ninety-four billion, eight hundred twenty-two million, thirty-two thousand, eight hundred twenty-one".