27720224 has 48 divisors (see below), whose sum is σ = 63721728. Its totient is φ = 11622912.

The previous prime is 27720211. The next prime is 27720233. The reversal of 27720224 is 42202772.

It is a happy number.

It is a Cunningham number, because it is equal to 5265²-1.

It is a super-2 number, since 2×27720224² = 1536821637220352, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 27720193 and 27720202.

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, 9212 + ... + 11844.

It is an arithmetic number, because the mean of its divisors is an integer number (1327536).

Almost surely, 2^27720224 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27720224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31860864).

27720224 is an abundant number, since it is smaller than the sum of its proper divisors (36001504).

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

27720224 is a wasteful number, since it uses less digits than its factorization.

27720224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2697 (or 2689 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 26.

The square root of 27720224 is about 5264.9999050332. Note that the first 4 decimals coincide. The cubic root of 27720224 is about 302.6441232042.

Adding to 27720224 its reverse (42202772), we get a palindrome (69922996).

The spelling of 27720224 in words is "twenty-seven million, seven hundred twenty thousand, two hundred twenty-four".