221221122122020 has 24 divisors (see below), whose sum is σ = 464564941957368. Its totient is φ = 88488337324800.

The previous prime is 221221122121949. The next prime is 221221122122027. The reversal of 221221122122020 is 20221221122122.

It can be written as a sum of positive squares in 4 ways, for example, as 141306855209536 + 79914266912484 = 11887256^2 + 8939478^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221221122121982 and 221221122122000.

It is not an unprimeable number, because it can be changed into a prime (221221122122027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10344480 + ... + 23440360.

It is an arithmetic number, because the mean of its divisors is an integer number (19356872581557).

Almost surely, 2^{221221122122020} is an apocalyptic number.

221221122122020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221122122020 is an abundant number, since it is smaller than the sum of its proper divisors (243343819835348).

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

221221122122020 is a wasteful number, since it uses less digits than its factorization.

221221122122020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13940511 (or 13940509 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 221221122122020 its reverse (20221221122122), we get a palindrome (241442343244142).

The spelling of 221221122122020 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred twenty-two million, one hundred twenty-two thousand, twenty".