21121413232121 has 2 divisors, whose sum is σ = 21121413232122. Its totient is φ = 21121413232120.

The previous prime is 21121413232099. The next prime is 21121413232169. The reversal of 21121413232121 is 12123231412112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14575291417600 + 6546121814521 = 3817760^2 + 2558539^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121413232121 - 2¹⁴ = 21121413215737 is a prime.

It is a super-2 number, since 2×21121413232121² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21121413232921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560706616060 + 10560706616061.

It is an arithmetic number, because the mean of its divisors is an integer number (10560706616061).

Almost surely, 2^{21121413232121} is an apocalyptic number.

It is an amenable number.

21121413232121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121413232121 is an equidigital number, since it uses as much as digits as its factorization.

21121413232121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 26.

Adding to 21121413232121 its reverse (12123231412112), we get a palindrome (33244644644233).

The spelling of 21121413232121 in words is "twenty-one trillion, one hundred twenty-one billion, four hundred thirteen million, two hundred thirty-two thousand, one hundred twenty-one".