20805328 has 10 divisors (see below), whose sum is σ = 40310354. Its totient is φ = 10402656.

The previous prime is 20805307. The next prime is 20805329. The reversal of 20805328 is 82350802.

It can be written as a sum of positive squares in only one way, i.e., 20178064 + 627264 = 4492^2 + 792^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20805296 and 20805305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20805329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 650151 + ... + 650182.

Almost surely, 2^20805328 is an apocalyptic number.

It is an amenable number.

20805328 is a deficient number, since it is larger than the sum of its proper divisors (19505026).

20805328 is a wasteful number, since it uses less digits than its factorization.

20805328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1300341 (or 1300335 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 20805328 is about 4561.2857836360. The cubic root of 20805328 is about 275.0372533554.

The spelling of 20805328 in words is "twenty million, eight hundred five thousand, three hundred twenty-eight".