22012812 has 18 divisors (see below), whose sum is σ = 55643588. Its totient is φ = 7337592.

The previous prime is 22012799. The next prime is 22012819. The reversal of 22012812 is 21821022.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (22012819) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 305698 + ... + 305769.

Almost surely, 2^22012812 is an apocalyptic number.

It is an amenable number.

22012812 is an abundant number, since it is smaller than the sum of its proper divisors (33630776).

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

22012812 is a wasteful number, since it uses less digits than its factorization.

22012812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611477 (or 611472 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 22012812 is about 4691.7813248275. The cubic root of 22012812 is about 280.2583160371.

Adding to 22012812 its reverse (21821022), we get a palindrome (43833834).

The spelling of 22012812 in words is "twenty-two million, twelve thousand, eight hundred twelve".