22721616 has 60 divisors (see below), whose sum is σ = 65793780. Its totient is φ = 7311360.

The previous prime is 22721603. The next prime is 22721617. The reversal of 22721616 is 61612722.

22721616 is a `hidden beast` number, since 2 + 27 + 21 + 616 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 14288400 + 8433216 = 3780^2 + 2904^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 22721616.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22721617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1456 + ... + 6896.

It is an arithmetic number, because the mean of its divisors is an integer number (1096563).

Almost surely, 2^22721616 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 22721616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32896890).

22721616 is an abundant number, since it is smaller than the sum of its proper divisors (43072164).

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

22721616 is a wasteful number, since it uses less digits than its factorization.

22721616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5484 (or 5475 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 22721616 is about 4766.7196267454. The cubic root of 22721616 is about 283.2346649131.

The spelling of 22721616 in words is "twenty-two million, seven hundred twenty-one thousand, six hundred sixteen".