21135489 has 8 divisors (see below), whose sum is σ = 28836192. Its totient is φ = 13762560.

The previous prime is 21135481. The next prime is 21135503. The reversal of 21135489 is 98453112.

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

It is not a de Polignac number, because 21135489 - 2³ = 21135481 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21135481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 81792 + ... + 82049.

It is an arithmetic number, because the mean of its divisors is an integer number (3604524).

Almost surely, 2^21135489 is an apocalyptic number.

It is an amenable number.

21135489 is a deficient number, since it is larger than the sum of its proper divisors (7700703).

21135489 is a wasteful number, since it uses less digits than its factorization.

21135489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163887.

The product of its digits is 8640, while the sum is 33.

The square root of 21135489 is about 4597.3349888821. The cubic root of 21135489 is about 276.4844856336.

The spelling of 21135489 in words is "twenty-one million, one hundred thirty-five thousand, four hundred eighty-nine".