2006404 has 6 divisors (see below), whose sum is σ = 3511214. Its totient is φ = 1003200.

The previous prime is 2006393. The next prime is 2006429. The reversal of 2006404 is 4046002.

It can be written as a sum of positive squares in only one way, i.e., 1557504 + 448900 = 1248^2 + 670^2 .

It is a super-2 number, since 2×2006404² = 8051314022432, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250797 + ... + 250804.

2^2006404 is an apocalyptic number.

It is an amenable number.

2006404 is a deficient number, since it is larger than the sum of its proper divisors (1504810).

2006404 is a wasteful number, since it uses less digits than its factorization.

2006404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501605 (or 501603 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 2006404 is about 1416.4759087256. The cubic root of 2006404 is about 126.1264372874.

It can be divided in two parts, 200 and 6404, that multiplied together give a triangular number (1280800 = T₁₆₀₀).

The spelling of 2006404 in words is "two million, six thousand, four hundred four".