21126135 has 8 divisors (see below), whose sum is σ = 33801840. Its totient is φ = 11267264.

The previous prime is 21126109. The next prime is 21126169. The reversal of 21126135 is 53162112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21126135 - 2⁵ = 21126103 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 704190 + ... + 704219.

It is an arithmetic number, because the mean of its divisors is an integer number (4225230).

Almost surely, 2^21126135 is an apocalyptic number.

21126135 is a deficient number, since it is larger than the sum of its proper divisors (12675705).

21126135 is a wasteful number, since it uses less digits than its factorization.

21126135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1408417.

The product of its digits is 360, while the sum is 21.

The square root of 21126135 is about 4596.3175477767. The cubic root of 21126135 is about 276.4436914114.

Adding to 21126135 its reverse (53162112), we get a palindrome (74288247).

The spelling of 21126135 in words is "twenty-one million, one hundred twenty-six thousand, one hundred thirty-five".