20666404 has 12 divisors (see below), whose sum is σ = 39454128. Its totient is φ = 9393800.

The previous prime is 20666389. The next prime is 20666413. The reversal of 20666404 is 40466602.

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 in 3 ways as a sum of consecutive naturals, for example, 234802 + ... + 234889.

It is an arithmetic number, because the mean of its divisors is an integer number (3287844).

Almost surely, 2^20666404 is an apocalyptic number.

It is an amenable number.

20666404 is a deficient number, since it is larger than the sum of its proper divisors (18787724).

20666404 is a wasteful number, since it uses less digits than its factorization.

20666404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469706 (or 469704 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 20666404 is about 4546.0316760885. The cubic root of 20666404 is about 274.4237144008.

The spelling of 20666404 in words is "twenty million, six hundred sixty-six thousand, four hundred four".