210021121121221 has 8 divisors (see below), whose sum is σ = 220093042777920. Its totient is φ = 200027580178272.

The previous prime is 210021121121191. The next prime is 210021121121269. The reversal of 210021121121221 is 122121121120012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 210021121121221 - 2¹³ = 210021121113029 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 (210021121121821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19595172951 + ... + 19595183668.

It is an arithmetic number, because the mean of its divisors is an integer number (27511630347240).

Almost surely, 2^{210021121121221} is an apocalyptic number.

It is an amenable number.

210021121121221 is a deficient number, since it is larger than the sum of its proper divisors (10071921656699).

210021121121221 is a wasteful number, since it uses less digits than its factorization.

210021121121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39190356875.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 210021121121221 its reverse (122121121120012), we get a palindrome (332142242241233).

The spelling of 210021121121221 in words is "two hundred ten trillion, twenty-one billion, one hundred twenty-one million, one hundred twenty-one thousand, two hundred twenty-one".