221021323020 has 72 divisors (see below), whose sum is σ = 699580548576. Its totient is φ = 56376452352.

The previous prime is 221021322989. The next prime is 221021323037. The reversal of 221021323020 is 20323120122.

221021323020 is a `hidden beast` number, since 221 + 0 + 213 + 230 + 2 + 0 = 666.

It is a super-2 number, since 2×221021323020² (a number of 23 digits) contains 22 as substring.

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 = 221021322984 and 221021323002.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26689257 + ... + 26697536.

It is an arithmetic number, because the mean of its divisors is an integer number (9716396508).

Almost surely, 2^221021323020 is an apocalyptic number.

221021323020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221021323020 is an abundant number, since it is smaller than the sum of its proper divisors (478559225556).

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

221021323020 is a wasteful number, since it uses less digits than its factorization.

221021323020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53386831 (or 53386826 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 221021323020 its reverse (20323120122), we get a palindrome (241344443142).

The spelling of 221021323020 in words is "two hundred twenty-one billion, twenty-one million, three hundred twenty-three thousand, twenty".