21120021221291 has 2 divisors, whose sum is σ = 21120021221292. Its totient is φ = 21120021221290.

The previous prime is 21120021221287. The next prime is 21120021221317. The reversal of 21120021221291 is 19212212002112.

It is an a-pointer prime, because the next prime (21120021221317) can be obtained adding 21120021221291 to its sum of digits (26).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21120021221291 - 2² = 21120021221287 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21120021221291.

It is not a weakly prime, because it can be changed into another prime (21120021251291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560010610645 + 10560010610646.

It is an arithmetic number, because the mean of its divisors is an integer number (10560010610646).

Almost surely, 2^{21120021221291} is an apocalyptic number.

21120021221291 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120021221291 is an equidigital number, since it uses as much as digits as its factorization.

21120021221291 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 26.

The spelling of 21120021221291 in words is "twenty-one trillion, one hundred twenty billion, twenty-one million, two hundred twenty-one thousand, two hundred ninety-one".