23121101222221 has 2 divisors, whose sum is σ = 23121101222222. Its totient is φ = 23121101222220.

The previous prime is 23121101222183. The next prime is 23121101222237. The reversal of 23121101222221 is 12222210112132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13487439875625 + 9633661346596 = 3672525^2 + 3103814^2 .

It is a cyclic number.

It is not a de Polignac number, because 23121101222221 - 2⁹ = 23121101221709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 23121101222192 and 23121101222201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23121101222291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11560550611110 + 11560550611111.

It is an arithmetic number, because the mean of its divisors is an integer number (11560550611111).

Almost surely, 2^{23121101222221} is an apocalyptic number.

It is an amenable number.

23121101222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

23121101222221 is an equidigital number, since it uses as much as digits as its factorization.

23121101222221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 23121101222221 its reverse (12222210112132), we get a palindrome (35343311334353).

The spelling of 23121101222221 in words is "twenty-three trillion, one hundred twenty-one billion, one hundred one million, two hundred twenty-two thousand, two hundred twenty-one".