221021210120 has 16 divisors (see below), whose sum is σ = 497297722860. Its totient is φ = 88408484032.

The previous prime is 221021210117. The next prime is 221021210129. The reversal of 221021210120 is 21012120122.

It can be written as a sum of positive squares in 2 ways, for example, as 206274022276 + 14747187844 = 454174^2 + 121438^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221021210095 and 221021210104.

It is not an unprimeable number, because it can be changed into a prime (221021210129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2762765087 + ... + 2762765166.

Almost surely, 2^221021210120 is an apocalyptic number.

221021210120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221021210120 is an abundant number, since it is smaller than the sum of its proper divisors (276276512740).

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

221021210120 is a wasteful number, since it uses less digits than its factorization.

221021210120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5525530264 (or 5525530260 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 221021210120 its reverse (21012120122), we get a palindrome (242033330242).

The spelling of 221021210120 in words is "two hundred twenty-one billion, twenty-one million, two hundred ten thousand, one hundred twenty".