20221345 has 4 divisors (see below), whose sum is σ = 24265620. Its totient is φ = 16177072.

The previous prime is 20221343. The next prime is 20221379. The reversal of 20221345 is 54312202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13424896 + 6796449 = 3664^2 + 2607^2 .

It is a cyclic number.

It is not a de Polignac number, because 20221345 - 2¹ = 20221343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20221343) 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 3 ways as a sum of consecutive naturals, for example, 2022130 + ... + 2022139.

It is an arithmetic number, because the mean of its divisors is an integer number (6066405).

Almost surely, 2^20221345 is an apocalyptic number.

It is an amenable number.

20221345 is a deficient number, since it is larger than the sum of its proper divisors (4044275).

20221345 is an equidigital number, since it uses as much as digits as its factorization.

20221345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4044274.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 20221345 is about 4496.8149839636. The cubic root of 20221345 is about 272.4394613434.

Adding to 20221345 its reverse (54312202), we get a palindrome (74533547).

The spelling of 20221345 in words is "twenty million, two hundred twenty-one thousand, three hundred forty-five".