20836221 has 16 divisors (see below), whose sum is σ = 32400000. Its totient is φ = 11905824.

The previous prime is 20836219. The next prime is 20836223. The reversal of 20836221 is 12263802.

It is an interprime number because it is at equal distance from previous prime (20836219) and next prime (20836223).

It is not a de Polignac number, because 20836221 - 2¹ = 20836219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20836191 and 20836200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20836223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9096 + ... + 11153.

It is an arithmetic number, because the mean of its divisors is an integer number (2025000).

Almost surely, 2^20836221 is an apocalyptic number.

20836221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20836221 is a deficient number, since it is larger than the sum of its proper divisors (11563779).

20836221 is an equidigital number, since it uses as much as digits as its factorization.

20836221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20273 (or 20259 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 20836221 is about 4564.6709629501. The cubic root of 20836221 is about 275.1733166409.

The spelling of 20836221 in words is "twenty million, eight hundred thirty-six thousand, two hundred twenty-one".