21002120121049 has 2 divisors, whose sum is σ = 21002120121050. Its totient is φ = 21002120121048.

The previous prime is 21002120121013. The next prime is 21002120121083. The reversal of 21002120121049 is 94012102120012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20868085785600 + 134034335449 = 4568160^2 + 366107^2 .

It is a cyclic number.

It is not a de Polignac number, because 21002120121049 - 2³⁹ = 20452364307161 is a prime.

It is not a weakly prime, because it can be changed into another prime (21002120121089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501060060524 + 10501060060525.

It is an arithmetic number, because the mean of its divisors is an integer number (10501060060525).

Almost surely, 2^{21002120121049} is an apocalyptic number.

It is an amenable number.

21002120121049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002120121049 is an equidigital number, since it uses as much as digits as its factorization.

21002120121049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 25.

The spelling of 21002120121049 in words is "twenty-one trillion, two billion, one hundred twenty million, one hundred twenty-one thousand, forty-nine".