21126562 has 16 divisors (see below), whose sum is σ = 33513984. Its totient is φ = 9972000.

The previous prime is 21126551. The next prime is 21126569. The reversal of 21126562 is 26562112.

It is not an unprimeable number, because it can be changed into a prime (21126569) 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, 1614 + ... + 6697.

It is an arithmetic number, because the mean of its divisors is an integer number (2094624).

Almost surely, 2^21126562 is an apocalyptic number.

21126562 is a deficient number, since it is larger than the sum of its proper divisors (12387422).

21126562 is a wasteful number, since it uses less digits than its factorization.

21126562 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8385.

The product of its digits is 1440, while the sum is 25.

The square root of 21126562 is about 4596.3639977704. The cubic root of 21126562 is about 276.4455538859.

Adding to 21126562 its reverse (26562112), we get a palindrome (47688674).

The spelling of 21126562 in words is "twenty-one million, one hundred twenty-six thousand, five hundred sixty-two".