221211112020 has 96 divisors (see below), whose sum is σ = 641476281600. Its totient is φ = 56890896384.

The previous prime is 221211112009. The next prime is 221211112021. The reversal of 221211112020 is 20211112122.

It is a super-2 number, since 2×221211112020² (a number of 23 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211112021) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 1471716 + ... + 1615044.

It is an arithmetic number, because the mean of its divisors is an integer number (6682044600).

Almost surely, 2^221211112020 is an apocalyptic number.

221211112020 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 221211112020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (320738140800).

221211112020 is an abundant number, since it is smaller than the sum of its proper divisors (420265169580).

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

221211112020 is a wasteful number, since it uses less digits than its factorization.

221211112020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144257 (or 144255 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 221211112020 its reverse (20211112122), we get a palindrome (241422224142).

The spelling of 221211112020 in words is "two hundred twenty-one billion, two hundred eleven million, one hundred twelve thousand, twenty".