210021122122221 has 4 divisors (see below), whose sum is σ = 280028162829632. Its totient is φ = 140014081414812.

The previous prime is 210021122122219. The next prime is 210021122122241. The reversal of 210021122122221 is 122221221120012.

210021122122221 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 210021122122221 - 2¹ = 210021122122219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210021122122241) 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, 35003520353701 + ... + 35003520353706.

It is an arithmetic number, because the mean of its divisors is an integer number (70007040707408).

Almost surely, 2^{210021122122221} is an apocalyptic number.

It is an amenable number.

210021122122221 is a deficient number, since it is larger than the sum of its proper divisors (70007040707411).

210021122122221 is an equidigital number, since it uses as much as digits as its factorization.

210021122122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70007040707410.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 210021122122221 its reverse (122221221120012), we get a palindrome (332242343242233).

The spelling of 210021122122221 in words is "two hundred ten trillion, twenty-one billion, one hundred twenty-two million, one hundred twenty-two thousand, two hundred twenty-one".