21652016 has 40 divisors (see below), whose sum is σ = 46363104. Its totient is φ = 9743360.

The previous prime is 21652003. The next prime is 21652061. The reversal of 21652016 is 61025612.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a junction number, because it is equal to n+sod(n) for n = 21651982 and 21652000.

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, 4526 + ... + 7986.

Almost surely, 2^21652016 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 21652016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23181552).

21652016 is an abundant number, since it is smaller than the sum of its proper divisors (24711088).

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

21652016 is a wasteful number, since it uses less digits than its factorization.

21652016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3509 (or 3503 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 21652016 is about 4653.1726810855. The cubic root of 21652016 is about 278.7187034782.

Adding to 21652016 its reverse (61025612), we get a palindrome (82677628).

The spelling of 21652016 in words is "twenty-one million, six hundred fifty-two thousand, sixteen".