20906804 has 24 divisors (see below), whose sum is σ = 39476808. Its totient is φ = 9651200.

The previous prime is 20906801. The next prime is 20906807. The reversal of 20906804 is 40860902.

It is an interprime number because it is at equal distance from previous prime (20906801) and next prime (20906807).

It can be written as a sum of positive squares in 4 ways, for example, as 14455204 + 6451600 = 3802^2 + 2540^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20906801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 704 + ... + 6504.

It is an arithmetic number, because the mean of its divisors is an integer number (1644867).

Almost surely, 2^20906804 is an apocalyptic number.

It is an amenable number.

20906804 is a deficient number, since it is larger than the sum of its proper divisors (18570004).

20906804 is a wasteful number, since it uses less digits than its factorization.

20906804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5875 (or 5873 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 20906804 is about 4572.3958708756. The cubic root of 20906804 is about 275.4836843093.

The spelling of 20906804 in words is "twenty million, nine hundred six thousand, eight hundred four".