20421796 has 12 divisors (see below), whose sum is σ = 36092700. Its totient is φ = 10109600.

The previous prime is 20421787. The next prime is 20421799. The reversal of 20421796 is 69712402.

It can be written as a sum of positive squares in 2 ways, for example, as 18062500 + 2359296 = 4250^2 + 1536^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421799) 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 3 ways as a sum of consecutive naturals, for example, 24871 + ... + 25678.

It is an arithmetic number, because the mean of its divisors is an integer number (3007725).

Almost surely, 2^20421796 is an apocalyptic number.

It is an amenable number.

20421796 is a deficient number, since it is larger than the sum of its proper divisors (15670904).

20421796 is a wasteful number, since it uses less digits than its factorization.

20421796 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50654 (or 50652 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 20421796 is about 4519.0481298610. The cubic root of 20421796 is about 273.3367195033.

The spelling of 20421796 in words is "twenty million, four hundred twenty-one thousand, seven hundred ninety-six".