221221101022020 has 144 divisors (see below), whose sum is σ = 732272193761472. Its totient is φ = 53612401086720.

The previous prime is 221221101021989. The next prime is 221221101022021. The reversal of 221221101022020 is 20220101122122.

It is a happy number.

221221101022020 is a `hidden beast` number, since 2 + 212 + 211 + 0 + 1 + 0 + 220 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 221221101021984 and 221221101022002.

It is not an unprimeable number, because it can be changed into a prime (221221101022021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11398947 + ... + 23924426.

It is an arithmetic number, because the mean of its divisors is an integer number (5085223567788).

Almost surely, 2^{221221101022020} is an apocalyptic number.

221221101022020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221101022020 is an abundant number, since it is smaller than the sum of its proper divisors (511051092739452).

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

221221101022020 is a wasteful number, since it uses less digits than its factorization.

221221101022020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35326562 (or 35326557 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221221101022020 its reverse (20220101122122), we get a palindrome (241441202144142).

The spelling of 221221101022020 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred one million, twenty-two thousand, twenty".