9221220 has 36 divisors (see below), whose sum is σ = 27971580. Its totient is φ = 2458944.

The previous prime is 9221207. The next prime is 9221227. The reversal of 9221220 is 221229.

It can be written as a sum of positive squares in 2 ways, for example, as 2377764 + 6843456 = 1542^2 + 2616^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 9221193 and 9221202.

It is not an unprimeable number, because it can be changed into a prime (9221227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25435 + ... + 25794.

Almost surely, 2^9221220 is an apocalyptic number.

9221220 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

9221220 is an abundant number, since it is smaller than the sum of its proper divisors (18750360).

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

9221220 is a wasteful number, since it uses less digits than its factorization.

9221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51244 (or 51239 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 9221220 is about 3036.6461762938. The cubic root of 9221220 is about 209.6988881803.

Adding to 9221220 its reverse (221229), we get a palindrome (9442449).

It can be divided in two parts, 92 and 21220, that added together give a palindrome (21312).

The spelling of 9221220 in words is "nine million, two hundred twenty-one thousand, two hundred twenty".