20221390 has 16 divisors (see below), whose sum is σ = 41598432. Its totient is φ = 6933024.

The previous prime is 20221379. The next prime is 20221391. The reversal of 20221390 is 9312202.

It is a happy number.

It is a super-2 number, since 2×20221390² = 817809227064200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20221391) 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 7 ways as a sum of consecutive naturals, for example, 144369 + ... + 144508.

It is an arithmetic number, because the mean of its divisors is an integer number (2599902).

Almost surely, 2^20221390 is an apocalyptic number.

20221390 is an abundant number, since it is smaller than the sum of its proper divisors (21377042).

20221390 is a wasteful number, since it uses less digits than its factorization.

20221390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288891.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 20221390 is about 4496.8199875023. The cubic root of 20221390 is about 272.4396634362.

Adding to 20221390 its reverse (9312202), we get a palindrome (29533592).

The spelling of 20221390 in words is "twenty million, two hundred twenty-one thousand, three hundred ninety".