21824474 has 8 divisors (see below), whose sum is σ = 37413408. Its totient is φ = 9353340.

The previous prime is 21824471. The next prime is 21824479. The reversal of 21824474 is 47442812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21824474.

It is not an unprimeable number, because it can be changed into a prime (21824471) 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, 779432 + ... + 779459.

It is an arithmetic number, because the mean of its divisors is an integer number (4676676).

Almost surely, 2^21824474 is an apocalyptic number.

21824474 is a deficient number, since it is larger than the sum of its proper divisors (15588934).

21824474 is a wasteful number, since it uses less digits than its factorization.

21824474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1558900.

The product of its digits is 14336, while the sum is 32.

The square root of 21824474 is about 4671.6671542395. The cubic root of 21824474 is about 279.4567442765.

The spelling of 21824474 in words is "twenty-one million, eight hundred twenty-four thousand, four hundred seventy-four".