21133534 has 4 divisors (see below), whose sum is σ = 31700304. Its totient is φ = 10566766.

The previous prime is 21133523. The next prime is 21133559. The reversal of 21133534 is 43533112.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5283382 + ... + 5283385.

It is an arithmetic number, because the mean of its divisors is an integer number (7925076).

Almost surely, 2^21133534 is an apocalyptic number.

21133534 is a deficient number, since it is larger than the sum of its proper divisors (10566770).

21133534 is a wasteful number, since it uses less digits than its factorization.

21133534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10566769.

The product of its digits is 1080, while the sum is 22.

The square root of 21133534 is about 4597.1223607818. The cubic root of 21133534 is about 276.4759605752.

Adding to 21133534 its reverse (43533112), we get a palindrome (64666646).

The spelling of 21133534 in words is "twenty-one million, one hundred thirty-three thousand, five hundred thirty-four".