21133011121 has 2 divisors, whose sum is σ = 21133011122. Its totient is φ = 21133011120.

The previous prime is 21133011103. The next prime is 21133011173. The reversal of 21133011121 is 12111033112.

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., 20054808225 + 1078202896 = 141615^2 + 32836^2 .

It is a cyclic number.

It is not a de Polignac number, because 21133011121 - 2¹³ = 21133002929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21133011095 and 21133011104.

It is not a weakly prime, because it can be changed into another prime (21133011181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10566505560 + 10566505561.

It is an arithmetic number, because the mean of its divisors is an integer number (10566505561).

Almost surely, 2^21133011121 is an apocalyptic number.

It is an amenable number.

21133011121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21133011121 is an equidigital number, since it uses as much as digits as its factorization.

21133011121 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21133011121 its reverse (12111033112), we get a palindrome (33244044233).

The spelling of 21133011121 in words is "twenty-one billion, one hundred thirty-three million, eleven thousand, one hundred twenty-one".