22012820 has 12 divisors (see below), whose sum is σ = 46226964. Its totient is φ = 8805120.

The previous prime is 22012819. The next prime is 22012829. The reversal of 22012820 is 2821022.

It can be written as a sum of positive squares in 2 ways, for example, as 3055504 + 18957316 = 1748^2 + 4354^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22012829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 550301 + ... + 550340.

It is an arithmetic number, because the mean of its divisors is an integer number (3852247).

Almost surely, 2^22012820 is an apocalyptic number.

22012820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22012820 is an abundant number, since it is smaller than the sum of its proper divisors (24214144).

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

22012820 is a wasteful number, since it uses less digits than its factorization.

22012820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100650 (or 1100648 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 22012820 is about 4691.7821773821. The cubic root of 22012820 is about 280.2583499881.

Adding to 22012820 its reverse (2821022), we get a palindrome (24833842).

The spelling of 22012820 in words is "twenty-two million, twelve thousand, eight hundred twenty".