221011020020 has 36 divisors (see below), whose sum is σ = 539898351300. Its totient is φ = 75775206528.

The previous prime is 221011020011. The next prime is 221011020023. The reversal of 221011020020 is 20020110122.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 114586312036 + 106424707984 = 338506^2 + 326228^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221011019983 and 221011020010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221011020023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112759745 + ... + 112761704.

It is an arithmetic number, because the mean of its divisors is an integer number (14997176425).

Almost surely, 2^221011020020 is an apocalyptic number.

221011020020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221011020020 is an abundant number, since it is smaller than the sum of its proper divisors (318887331280).

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

221011020020 is a wasteful number, since it uses less digits than its factorization.

221011020020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225521472 (or 225521463 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 221011020020 its reverse (20020110122), we get a palindrome (241031130142).

The spelling of 221011020020 in words is "two hundred twenty-one billion, eleven million, twenty thousand, twenty".