394066881 has 12 divisors (see below), whose sum is σ = 612993108. Its totient is φ = 242502624.

The previous prime is 394066873. The next prime is 394066901. The reversal of 394066881 is 188660493.

It can be written as a sum of positive squares in 2 ways, for example, as 184280625 + 209786256 = 13575^2 + 14484^2 .

It is not a de Polignac number, because 394066881 - 2³ = 394066873 is a prime.

It is a super-2 number, since 2×394066881² = 310577413402136322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (394066801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1683930 + ... + 1684163.

It is an arithmetic number, because the mean of its divisors is an integer number (51082759).

Almost surely, 2^394066881 is an apocalyptic number.

It is an amenable number.

394066881 is a deficient number, since it is larger than the sum of its proper divisors (218926227).

394066881 is a wasteful number, since it uses less digits than its factorization.

394066881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3368112 (or 3368109 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 394066881 is about 19851.1178778425. The cubic root of 394066881 is about 733.1451718121.

The spelling of 394066881 in words is "three hundred ninety-four million, sixty-six thousand, eight hundred eighty-one".