21193224 has 32 divisors (see below), whose sum is σ = 57059520. Its totient is φ = 6520896.

The previous prime is 21193223. The next prime is 21193231. The reversal of 21193224 is 42239112.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 21193194 and 21193203.

It is not an unprimeable number, because it can be changed into a prime (21193223) 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, 33652 + ... + 34275.

It is an arithmetic number, because the mean of its divisors is an integer number (1783110).

Almost surely, 2^21193224 is an apocalyptic number.

21193224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21193224 is an abundant number, since it is smaller than the sum of its proper divisors (35866296).

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

21193224 is a wasteful number, since it uses less digits than its factorization.

21193224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67949 (or 67945 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The square root of 21193224 is about 4603.6098879032. The cubic root of 21193224 is about 276.7360107466.

The spelling of 21193224 in words is "twenty-one million, one hundred ninety-three thousand, two hundred twenty-four".