21049224 has 64 divisors (see below), whose sum is σ = 61392000. Its totient is φ = 6011712.

The previous prime is 21049219. The next prime is 21049241. The reversal of 21049224 is 42294012.

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 = 21049194 and 21049203.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6954 + ... + 9510.

It is an arithmetic number, because the mean of its divisors is an integer number (959250).

Almost surely, 2^21049224 is an apocalyptic number.

21049224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21049224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30696000).

21049224 is an abundant number, since it is smaller than the sum of its proper divisors (40342776).

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

21049224 is a wasteful number, since it uses less digits than its factorization.

21049224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2587 (or 2569 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21049224 is about 4587.9433300772. The cubic root of 21049224 is about 276.1078133721.

The spelling of 21049224 in words is "twenty-one million, forty-nine thousand, two hundred twenty-four".