20107221 has 16 divisors (see below), whose sum is σ = 28081536. Its totient is φ = 12773376.

The previous prime is 20107207. The next prime is 20107223. The reversal of 20107221 is 12270102.

It is not a de Polignac number, because 20107221 - 2⁷ = 20107093 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20107221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20107223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29541 + ... + 30213.

It is an arithmetic number, because the mean of its divisors is an integer number (1755096).

Almost surely, 2^20107221 is an apocalyptic number.

It is an amenable number.

20107221 is a deficient number, since it is larger than the sum of its proper divisors (7974315).

20107221 is a wasteful number, since it uses less digits than its factorization.

20107221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1132.

The product of its (nonzero) digits is 56, while the sum is 15.

The square root of 20107221 is about 4484.1076035260. The cubic root of 20107221 is about 271.9259683543.

Adding to 20107221 its reverse (12270102), we get a palindrome (32377323).

The spelling of 20107221 in words is "twenty million, one hundred seven thousand, two hundred twenty-one".