2121220020 has 24 divisors (see below), whose sum is σ = 5939416224. Its totient is φ = 565658656.

The previous prime is 2121219977. The next prime is 2121220081. The reversal of 2121220020 is 200221212.

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 = 2121219978 and 2121220005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17676774 + ... + 17676893.

It is an arithmetic number, because the mean of its divisors is an integer number (247475676).

Almost surely, 2^2121220020 is an apocalyptic number.

2121220020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121220020 is an abundant number, since it is smaller than the sum of its proper divisors (3818196204).

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

2121220020 is a wasteful number, since it uses less digits than its factorization.

2121220020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35353679 (or 35353677 counting only the distinct ones).

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

The square root of 2121220020 is about 46056.7043979484. The cubic root of 2121220020 is about 1284.8780375498.

Adding to 2121220020 its reverse (200221212), we get a palindrome (2321441232).

The spelling of 2121220020 in words is "two billion, one hundred twenty-one million, two hundred twenty thousand, twenty".