3231221220 has 120 divisors (see below), whose sum is σ = 10153653048. Its totient is φ = 860198400.

The previous prime is 3231221219. The next prime is 3231221243. The reversal of 3231221220 is 221221323.

3231221220 is a `hidden beast` number, since 323 + 122 + 1 + 220 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 54997056 + 3176224164 = 7416^2 + 56358^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 3231221193 and 3231221202.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1231510 + ... + 1234130.

Almost surely, 2^3231221220 is an apocalyptic number.

3231221220 is a gapful number since it is divisible by the number (30) 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 3231221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5076826524).

3231221220 is an abundant number, since it is smaller than the sum of its proper divisors (6922431828).

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

3231221220 is a wasteful number, since it uses less digits than its factorization.

3231221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3403 (or 3392 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 3231221220 is about 56843.8318553561. The cubic root of 3231221220 is about 1478.3895954266.

Adding to 3231221220 its reverse (221221323), we get a palindrome (3452442543).

The spelling of 3231221220 in words is "three billion, two hundred thirty-one million, two hundred twenty-one thousand, two hundred twenty".