21835229 has 4 divisors (see below), whose sum is σ = 23514876. Its totient is φ = 20155584.

The previous prime is 21835223. The next prime is 21835267. The reversal of 21835229 is 92253812.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7166329 + 14668900 = 2677^2 + 3830^2 .

It is a cyclic number.

It is not a de Polignac number, because 21835229 - 2²⁴ = 5058013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21835195 and 21835204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21835223) 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, 839804 + ... + 839829.

It is an arithmetic number, because the mean of its divisors is an integer number (5878719).

Almost surely, 2^21835229 is an apocalyptic number.

It is an amenable number.

21835229 is a deficient number, since it is larger than the sum of its proper divisors (1679647).

21835229 is a wasteful number, since it uses less digits than its factorization.

21835229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1679646.

The product of its digits is 8640, while the sum is 32.

The square root of 21835229 is about 4672.8181004614. The cubic root of 21835229 is about 279.5026417357.

The spelling of 21835229 in words is "twenty-one million, eight hundred thirty-five thousand, two hundred twenty-nine".