20809432 has 32 divisors (see below), whose sum is σ = 46033920. Its totient is φ = 8629920.

The previous prime is 20809423. The next prime is 20809433. The reversal of 20809432 is 23490802.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a self number, because there is not a number n which added to its sum of digits gives 20809432.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20809433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4258 + ... + 7729.

It is an arithmetic number, because the mean of its divisors is an integer number (1438560).

Almost surely, 2^20809432 is an apocalyptic number.

It is an amenable number.

20809432 is an abundant number, since it is smaller than the sum of its proper divisors (25224488).

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

20809432 is a wasteful number, since it uses less digits than its factorization.

20809432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12031 (or 12027 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 20809432 is about 4561.7356346023. The cubic root of 20809432 is about 275.0553365226.

The spelling of 20809432 in words is "twenty million, eight hundred nine thousand, four hundred thirty-two".