394645561 has 6 divisors (see below), whose sum is σ = 416509962. Its totient is φ = 373874400.

The previous prime is 394645487. The next prime is 394645609. The reversal of 394645561 is 165546493.

It can be written as a sum of positive squares in only one way, i.e., 343879936 + 50765625 = 18544^2 + 7125^2 .

It is not a de Polignac number, because 394645561 - 2¹⁷ = 394514489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394645061) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 546240 + ... + 546961.

It is an arithmetic number, because the mean of its divisors is an integer number (69418327).

Almost surely, 2^394645561 is an apocalyptic number.

It is an amenable number.

394645561 is a deficient number, since it is larger than the sum of its proper divisors (21864401).

394645561 is a wasteful number, since it uses less digits than its factorization.

394645561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1093239 (or 1093220 counting only the distinct ones).

The product of its digits is 388800, while the sum is 43.

The square root of 394645561 is about 19865.6880323839. The cubic root of 394645561 is about 733.5038663780.

The spelling of 394645561 in words is "three hundred ninety-four million, six hundred forty-five thousand, five hundred sixty-one".