21055235 has 8 divisors (see below), whose sum is σ = 26364960. Its totient is φ = 16111744.

The previous prime is 21055217. The next prime is 21055259. The reversal of 21055235 is 53255012.

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 21055235 - 2¹⁴ = 21038851 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a self number, because there is not a number n which added to its sum of digits gives 21055235.

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, 91430 + ... + 91659.

It is an arithmetic number, because the mean of its divisors is an integer number (3295620).

Almost surely, 2^21055235 is an apocalyptic number.

21055235 is a deficient number, since it is larger than the sum of its proper divisors (5309725).

21055235 is a wasteful number, since it uses less digits than its factorization.

21055235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183117.

The product of its (nonzero) digits is 1500, while the sum is 23.

The square root of 21055235 is about 4588.5983698729. The cubic root of 21055235 is about 276.1340934558.

The spelling of 21055235 in words is "twenty-one million, fifty-five thousand, two hundred thirty-five".