2031221220 has 192 divisors, whose sum is σ = 6871603200. Its totient is φ = 437944320.

The previous prime is 2031221207. The next prime is 2031221233. The reversal of 2031221220 is 221221302.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (2031221207) and next prime (2031221233).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 2031221220.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2640996 + ... + 2641764.

It is an arithmetic number, because the mean of its divisors is an integer number (35789600).

Almost surely, 2^2031221220 is an apocalyptic number.

2031221220 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 2031221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3435801600).

2031221220 is an abundant number, since it is smaller than the sum of its proper divisors (4840381980).

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

2031221220 is a wasteful number, since it uses less digits than its factorization.

2031221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1138 (or 1136 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 2031221220 is about 45069.0716567360. The cubic root of 2031221220 is about 1266.4432734695.

Adding to 2031221220 its reverse (221221302), we get a palindrome (2252442522).

The spelling of 2031221220 in words is "two billion, thirty-one million, two hundred twenty-one thousand, two hundred twenty".