21201122099873 has 2 divisors, whose sum is σ = 21201122099874. Its totient is φ = 21201122099872.

The previous prime is 21201122099819. The next prime is 21201122099999. The reversal of 21201122099873 is 37899022110212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18992756692624 + 2208365407249 = 4358068^2 + 1486057^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201122099873 - 2⁸ = 21201122099617 is a prime.

It is a super-6 number, since 6×21201122099873⁶ (a number of 81 digits) contains 666666 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (21201122099813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600561049936 + 10600561049937.

It is an arithmetic number, because the mean of its divisors is an integer number (10600561049937).

Almost surely, 2^{21201122099873} is an apocalyptic number.

It is an amenable number.

21201122099873 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201122099873 is an equidigital number, since it uses as much as digits as its factorization.

21201122099873 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 47.

The spelling of 21201122099873 in words is "twenty-one trillion, two hundred one billion, one hundred twenty-two million, ninety-nine thousand, eight hundred seventy-three".