21153235 has 8 divisors (see below), whose sum is σ = 25415856. Its totient is φ = 16901280.

The previous prime is 21153227. The next prime is 21153257. The reversal of 21153235 is 53235112.

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

It is not a de Polignac number, because 21153235 - 2³ = 21153227 is a prime.

It is a Duffinian 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, 2677 + ... + 7033.

It is an arithmetic number, because the mean of its divisors is an integer number (3176982).

Almost surely, 2^21153235 is an apocalyptic number.

21153235 is a deficient number, since it is larger than the sum of its proper divisors (4262621).

21153235 is an equidigital number, since it uses as much as digits as its factorization.

21153235 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5333.

The product of its digits is 900, while the sum is 22.

The square root of 21153235 is about 4599.2646151314. The cubic root of 21153235 is about 276.5618455835.

Adding to 21153235 its reverse (53235112), we get a palindrome (74388347).

The spelling of 21153235 in words is "twenty-one million, one hundred fifty-three thousand, two hundred thirty-five".