2121020220 has 96 divisors (see below), whose sum is σ = 6492648960. Its totient is φ = 513084160.

The previous prime is 2121020219. The next prime is 2121020221. The reversal of 2121020220 is 220201212.

It is an interprime number because it is at equal distance from previous prime (2121020219) and next prime (2121020221).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 2121020196 and 2121020205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121020221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 328786 + ... + 335174.

It is an arithmetic number, because the mean of its divisors is an integer number (67631760).

Almost surely, 2^2121020220 is an apocalyptic number.

2121020220 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 2121020220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3246324480).

2121020220 is an abundant number, since it is smaller than the sum of its proper divisors (4371628740).

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

2121020220 is a wasteful number, since it uses less digits than its factorization.

2121020220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6915 (or 6913 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 2121020220 is about 46054.5352815551. The cubic root of 2121020220 is about 1284.8376949340.

Adding to 2121020220 its reverse (220201212), we get a palindrome (2341221432).

The spelling of 2121020220 in words is "two billion, one hundred twenty-one million, twenty thousand, two hundred twenty".