21283853 has 4 divisors (see below), whose sum is σ = 21305760. Its totient is φ = 21261948.

The previous prime is 21283841. The next prime is 21283859. The reversal of 21283853 is 35838212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21283853 - 2⁸ = 21283597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21283859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9425 + ... + 11462.

It is an arithmetic number, because the mean of its divisors is an integer number (5326440).

Almost surely, 2^21283853 is an apocalyptic number.

It is an amenable number.

21283853 is a deficient number, since it is larger than the sum of its proper divisors (21907).

21283853 is a wasteful number, since it uses less digits than its factorization.

21283853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21906.

The product of its digits is 11520, while the sum is 32.

The square root of 21283853 is about 4613.4426408052. The cubic root of 21283853 is about 277.1299203305.

The spelling of 21283853 in words is "twenty-one million, two hundred eighty-three thousand, eight hundred fifty-three".