2121201012221 has 4 divisors (see below), whose sum is σ = 2122255813344. Its totient is φ = 2120146211100.

The previous prime is 2121201012169. The next prime is 2121201012233. The reversal of 2121201012221 is 1222101021212.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121201012221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2121201012221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121201015221) 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, 527397545 + ... + 527401566.

It is an arithmetic number, because the mean of its divisors is an integer number (530563953336).

Almost surely, 2^{2121201012221} is an apocalyptic number.

It is an amenable number.

2121201012221 is a deficient number, since it is larger than the sum of its proper divisors (1054801123).

2121201012221 is a wasteful number, since it uses less digits than its factorization.

2121201012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1054801122.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 2121201012221 its reverse (1222101021212), we get a palindrome (3343302033433).

The spelling of 2121201012221 in words is "two trillion, one hundred twenty-one billion, two hundred one million, twelve thousand, two hundred twenty-one".