22021440 has 224 divisors, whose sum is σ = 83393280. Its totient is φ = 4816896.

The previous prime is 22021429. The next prime is 22021457. The reversal of 22021440 is 4412022.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a zygodrome in base 4.

It is a congruent number.

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, 194824 + ... + 194936.

Almost surely, 2^22021440 is an apocalyptic number.

22021440 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 22021440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41696640).

22021440 is an abundant number, since it is smaller than the sum of its proper divisors (61371840).

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

22021440 is a wasteful number, since it uses less digits than its factorization.

22021440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 22021440 is about 4692.7007149402. The cubic root of 22021440 is about 280.2949273357.

Adding to 22021440 its reverse (4412022), we get a palindrome (26433462).

The spelling of 22021440 in words is "twenty-two million, twenty-one thousand, four hundred forty".