21020422 has 16 divisors (see below), whose sum is σ = 33326640. Its totient is φ = 9916128.

The previous prime is 21020411. The next prime is 21020429. The reversal of 21020422 is 22402012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020429) 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 7 ways as a sum of consecutive naturals, for example, 9528 + ... + 11524.

It is an arithmetic number, because the mean of its divisors is an integer number (2082915).

Almost surely, 2^21020422 is an apocalyptic number.

21020422 is a deficient number, since it is larger than the sum of its proper divisors (12306218).

21020422 is a wasteful number, since it uses less digits than its factorization.

21020422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2295.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 21020422 is about 4584.8033763729. The cubic root of 21020422 is about 275.9818215991.

Adding to 21020422 its reverse (22402012), we get a palindrome (43422434).

The spelling of 21020422 in words is "twenty-one million, twenty thousand, four hundred twenty-two".