21624130 has 16 divisors (see below), whose sum is σ = 42462144. Its totient is φ = 7863280.

The previous prime is 21624107. The next prime is 21624137. The reversal of 21624130 is 3142612.

It is a junction number, because it is equal to n+sod(n) for n = 21624098 and 21624107.

It is not an unprimeable number, because it can be changed into a prime (21624137) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98182 + ... + 98401.

It is an arithmetic number, because the mean of its divisors is an integer number (2653884).

Almost surely, 2^21624130 is an apocalyptic number.

21624130 is a deficient number, since it is larger than the sum of its proper divisors (20838014).

21624130 is a wasteful number, since it uses less digits than its factorization.

21624130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196601.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21624130 is about 4650.1752655142. The cubic root of 21624130 is about 278.5989965517.

Adding to 21624130 its reverse (3142612), we get a palindrome (24766742).

The spelling of 21624130 in words is "twenty-one million, six hundred twenty-four thousand, one hundred thirty".