210021220021221 has 48 divisors (see below), whose sum is σ = 383056605944064. Its totient is φ = 108041606779392.

The previous prime is 210021220021127. The next prime is 210021220021253. The reversal of 210021220021221 is 122120022120012.

It is a happy number.

210021220021221 is a `hidden beast` number, since 2 + 10 + 0 + 212 + 200 + 21 + 221 = 666.

It is not a de Polignac number, because 210021220021221 - 2¹⁴ = 210021220004837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 210021220021194 and 210021220021203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210021220001221) 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, 4262980686 + ... + 4263029951.

It is an arithmetic number, because the mean of its divisors is an integer number (7980345957168).

Almost surely, 2^{210021220021221} is an apocalyptic number.

210021220021221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

210021220021221 is a deficient number, since it is larger than the sum of its proper divisors (173035385922843).

210021220021221 is a wasteful number, since it uses less digits than its factorization.

210021220021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8526010690 (or 8526010687 counting only the distinct ones).

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

Adding to 210021220021221 its reverse (122120022120012), we get a palindrome (332141242141233).

The spelling of 210021220021221 in words is "two hundred ten trillion, twenty-one billion, two hundred twenty million, twenty-one thousand, two hundred twenty-one".