221021222220020 has 24 divisors (see below), whose sum is σ = 464262280387584. Its totient is φ = 88386067226016.

The previous prime is 221021222219933. The next prime is 221021222220091. The reversal of 221021222220020 is 20022222120122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221021222219974 and 221021222220001.

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, 1401273044 + ... + 1401430763.

It is an arithmetic number, because the mean of its divisors is an integer number (19344261682816).

Almost surely, 2^{221021222220020} is an apocalyptic number.

221021222220020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221021222220020 is an abundant number, since it is smaller than the sum of its proper divisors (243241058167564).

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

221021222220020 is a wasteful number, since it uses less digits than its factorization.

221021222220020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2802707759 (or 2802707757 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 221021222220020 its reverse (20022222120122), we get a palindrome (241043444340142).

The spelling of 221021222220020 in words is "two hundred twenty-one trillion, twenty-one billion, two hundred twenty-two million, two hundred twenty thousand, twenty".