20889936 has 30 divisors (see below), whose sum is σ = 58463210. Its totient is φ = 6963264.

The previous prime is 20889929. The next prime is 20889937. The reversal of 20889936 is 63998802.

It can be written as a sum of positive squares in only one way, i.e., 18147600 + 2742336 = 4260^2 + 1656^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20889891 and 20889900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20889937) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 72391 + ... + 72678.

Almost surely, 2^20889936 is an apocalyptic number.

It is an amenable number.

20889936 is an abundant number, since it is smaller than the sum of its proper divisors (37573274).

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

20889936 is a wasteful number, since it uses less digits than its factorization.

20889936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145083 (or 145074 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 20889936 is about 4570.5509514718. The cubic root of 20889936 is about 275.4095759142.

The spelling of 20889936 in words is "twenty million, eight hundred eighty-nine thousand, nine hundred thirty-six".