1890838105991 has 2 divisors, whose sum is σ = 1890838105992. Its totient is φ = 1890838105990.

The previous prime is 1890838105967. The next prime is 1890838105993. The reversal of 1890838105991 is 1995018380981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1890838105991 - 2¹⁸ = 1890837843847 is a prime.

Together with 1890838105993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1890838105993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945419052995 + 945419052996.

It is an arithmetic number, because the mean of its divisors is an integer number (945419052996).

Almost surely, 2^{1890838105991} is an apocalyptic number.

1890838105991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1890838105991 is an equidigital number, since it uses as much as digits as its factorization.

1890838105991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5598720, while the sum is 62.

The spelling of 1890838105991 in words is "one trillion, eight hundred ninety billion, eight hundred thirty-eight million, one hundred five thousand, nine hundred ninety-one".