21634230 has 16 divisors (see below), whose sum is σ = 51922224. Its totient is φ = 5769120.

The previous prime is 21634213. The next prime is 21634253. The reversal of 21634230 is 3243612.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21634197 and 21634206.

It is a congruent 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, 360541 + ... + 360600.

It is an arithmetic number, because the mean of its divisors is an integer number (3245139).

Almost surely, 2^21634230 is an apocalyptic number.

21634230 is an abundant number, since it is smaller than the sum of its proper divisors (30287994).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21634230 is a wasteful number, since it uses less digits than its factorization.

21634230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721151.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 21634230 is about 4651.2611193095. The cubic root of 21634230 is about 278.6423649537.

Adding to 21634230 its reverse (3243612), we get a palindrome (24877842).

The spelling of 21634230 in words is "twenty-one million, six hundred thirty-four thousand, two hundred thirty".