20101102210991 has 2 divisors, whose sum is σ = 20101102210992. Its totient is φ = 20101102210990.

The previous prime is 20101102210823. The next prime is 20101102211033. The reversal of 20101102210991 is 19901220110102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20101102210991 - 2¹⁸ = 20101101948847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20101102260991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050551105495 + 10050551105496.

It is an arithmetic number, because the mean of its divisors is an integer number (10050551105496).

Almost surely, 2^{20101102210991} is an apocalyptic number.

20101102210991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20101102210991 is an equidigital number, since it uses as much as digits as its factorization.

20101102210991 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 29.

The spelling of 20101102210991 in words is "twenty trillion, one hundred one billion, one hundred two million, two hundred ten thousand, nine hundred ninety-one".