21301113121 has 2 divisors, whose sum is σ = 21301113122. Its totient is φ = 21301113120.

The previous prime is 21301113109. The next prime is 21301113179. The reversal of 21301113121 is 12131110312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21229947025 + 71166096 = 145705^2 + 8436^2 .

It is a cyclic number.

It is not a de Polignac number, because 21301113121 - 2¹⁷ = 21300982049 is a prime.

It is a super-3 number, since 3×21301113121³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21301113095 and 21301113104.

It is not a weakly prime, because it can be changed into another prime (21301113521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650556560 + 10650556561.

It is an arithmetic number, because the mean of its divisors is an integer number (10650556561).

Almost surely, 2^21301113121 is an apocalyptic number.

It is an amenable number.

21301113121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21301113121 is an equidigital number, since it uses as much as digits as its factorization.

21301113121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 21301113121 its reverse (12131110312), we get a palindrome (33432223433).

The spelling of 21301113121 in words is "twenty-one billion, three hundred one million, one hundred thirteen thousand, one hundred twenty-one".