21011020332191 has 2 divisors, whose sum is σ = 21011020332192. Its totient is φ = 21011020332190.

The previous prime is 21011020332119. The next prime is 21011020332221. The reversal of 21011020332191 is 19123302011012.

Together with previous prime (21011020332119) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011020332191 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21011020332191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011020332791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505510166095 + 10505510166096.

It is an arithmetic number, because the mean of its divisors is an integer number (10505510166096).

Almost surely, 2^{21011020332191} is an apocalyptic number.

21011020332191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011020332191 is an equidigital number, since it uses as much as digits as its factorization.

21011020332191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 26.

The spelling of 21011020332191 in words is "twenty-one trillion, eleven billion, twenty million, three hundred thirty-two thousand, one hundred ninety-one".