21622380 has 96 divisors (see below), whose sum is σ = 68678400. Its totient is φ = 5038848.

The previous prime is 21622339. The next prime is 21622417. The reversal of 21622380 is 8322612.

It is a self number, because there is not a number n which added to its sum of digits gives 21622380.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14091 + ... + 15549.

It is an arithmetic number, because the mean of its divisors is an integer number (715400).

Almost surely, 2^21622380 is an apocalyptic number.

21622380 is a gapful number since it is divisible by the number (20) 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 21622380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34339200).

21622380 is an abundant number, since it is smaller than the sum of its proper divisors (47056020).

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

21622380 is a wasteful number, since it uses less digits than its factorization.

21622380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1503 (or 1501 counting only the distinct ones).

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

The square root of 21622380 is about 4649.9870967563. The cubic root of 21622380 is about 278.5914808520.

Adding to 21622380 its reverse (8322612), we get a palindrome (29944992).

The spelling of 21622380 in words is "twenty-one million, six hundred twenty-two thousand, three hundred eighty".