21126552 has 32 divisors (see below), whose sum is σ = 53101680. Its totient is φ = 7004160.

The previous prime is 21126551. The next prime is 21126569. The reversal of 21126552 is 25562112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21126551) 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, 2352 + ... + 6912.

Almost surely, 2^21126552 is an apocalyptic number.

It is an amenable number.

21126552 is an abundant number, since it is smaller than the sum of its proper divisors (31975128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21126552 is a wasteful number, since it uses less digits than its factorization.

21126552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4763 (or 4759 counting only the distinct ones).

The product of its digits is 1200, while the sum is 24.

The square root of 21126552 is about 4596.3629099539. The cubic root of 21126552 is about 276.4455102685.

Adding to 21126552 its reverse (25562112), we get a palindrome (46688664).

The spelling of 21126552 in words is "twenty-one million, one hundred twenty-six thousand, five hundred fifty-two".