20805336 has 80 divisors (see below), whose sum is σ = 59052840. Its totient is φ = 6842880.

The previous prime is 20805329. The next prime is 20805341. The reversal of 20805336 is 63350802.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 62691 + ... + 63021.

Almost surely, 2^20805336 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20805336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29526420).

20805336 is an abundant number, since it is smaller than the sum of its proper divisors (38247504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20805336 is a wasteful number, since it uses less digits than its factorization.

20805336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446 (or 433 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20805336 is about 4561.2866605816. The cubic root of 20805336 is about 275.0372886075.

The spelling of 20805336 in words is "twenty million, eight hundred five thousand, three hundred thirty-six".