102020011021991 has 2 divisors, whose sum is σ = 102020011021992. Its totient is φ = 102020011021990.

The previous prime is 102020011021889. The next prime is 102020011022003. The reversal of 102020011021991 is 199120110020201.

It is a strong prime.

It is an emirp because it is prime and its reverse (199120110020201) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102020011021991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102020011821991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51010005510995 + 51010005510996.

It is an arithmetic number, because the mean of its divisors is an integer number (51010005510996).

Almost surely, 2^{102020011021991} is an apocalyptic number.

102020011021991 is a deficient number, since it is larger than the sum of its proper divisors (1).

102020011021991 is an equidigital number, since it uses as much as digits as its factorization.

102020011021991 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 102020011021991 in words is "one hundred two trillion, twenty billion, eleven million, twenty-one thousand, nine hundred ninety-one".