21126567 has 16 divisors (see below), whose sum is σ = 35119872. Its totient is φ = 10974720.

The previous prime is 21126551. The next prime is 21126569. The reversal of 21126567 is 76562112.

It is not a de Polignac number, because 21126567 - 2⁴ = 21126551 is a prime.

It is a congruent number.

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 (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45498 + ... + 45959.

It is an arithmetic number, because the mean of its divisors is an integer number (2194992).

Almost surely, 2^21126567 is an apocalyptic number.

21126567 is a deficient number, since it is larger than the sum of its proper divisors (13993305).

21126567 is a wasteful number, since it uses less digits than its factorization.

21126567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91478.

The product of its digits is 5040, while the sum is 30.

The square root of 21126567 is about 4596.3645416786. The cubic root of 21126567 is about 276.4455756945.

Adding to 21126567 its reverse (76562112), we get a palindrome (97688679).

The spelling of 21126567 in words is "twenty-one million, one hundred twenty-six thousand, five hundred sixty-seven".