211221102020 has 24 divisors (see below), whose sum is σ = 443796263064. Its totient is φ = 84444260096.

The previous prime is 211221102017. The next prime is 211221102067. The reversal of 211221102020 is 20201122112.

It can be written as a sum of positive squares in 4 ways, for example, as 46152788224 + 165068313796 = 214832^2 + 406286^2 .

It is a super-2 number, since 2×211221102020² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211221101986 and 211221102004.

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, 2722079 + ... + 2798598.

It is an arithmetic number, because the mean of its divisors is an integer number (18491510961).

Almost surely, 2^211221102020 is an apocalyptic number.

211221102020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211221102020 is an abundant number, since it is smaller than the sum of its proper divisors (232575161044).

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

211221102020 is a wasteful number, since it uses less digits than its factorization.

211221102020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5522599 (or 5522597 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 211221102020 its reverse (20201122112), we get a palindrome (231422224132).

The spelling of 211221102020 in words is "two hundred eleven billion, two hundred twenty-one million, one hundred two thousand, twenty".