1002111211991 has 2 divisors, whose sum is σ = 1002111211992. Its totient is φ = 1002111211990.

The previous prime is 1002111211963. The next prime is 1002111212119. The reversal of 1002111211991 is 1991121112001.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1002111211991 - 2¹⁰ = 1002111210967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1002111211931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 501055605995 + 501055605996.

It is an arithmetic number, because the mean of its divisors is an integer number (501055605996).

Almost surely, 2^{1002111211991} is an apocalyptic number.

1002111211991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1002111211991 is an equidigital number, since it uses as much as digits as its factorization.

1002111211991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 29.

Adding to 1002111211991 its reverse (1991121112001), we get a palindrome (2993232323992).

The spelling of 1002111211991 in words is "one trillion, two billion, one hundred eleven million, two hundred eleven thousand, nine hundred ninety-one".