22017820 has 48 divisors (see below), whose sum is σ = 51692256. Its totient is φ = 7808000.

The previous prime is 22017811. The next prime is 22017823. The reversal of 22017820 is 2871022.

It is a super-4 number, since 4×22017820⁴ (a number of 30 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 22017791 and 22017800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22017823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7800 + ... + 10240.

It is an arithmetic number, because the mean of its divisors is an integer number (1076922).

Almost surely, 2^22017820 is an apocalyptic number.

22017820 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 22017820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25846128).

22017820 is an abundant number, since it is smaller than the sum of its proper divisors (29674436).

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

22017820 is a wasteful number, since it uses less digits than its factorization.

22017820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2502 (or 2500 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 22017820 is about 4692.3149936891. The cubic root of 22017820 is about 280.2795677098.

Adding to 22017820 its reverse (2871022), we get a palindrome (24888842).

It can be divided in two parts, 220 and 17820, that multiplied together give a square (3920400 = 1980²).

The spelling of 22017820 in words is "twenty-two million, seventeen thousand, eight hundred twenty".