1995878785991 has 2 divisors, whose sum is σ = 1995878785992. Its totient is φ = 1995878785990.

The previous prime is 1995878785969. The next prime is 1995878785997.

1995878785991 is nontrivially palindromic in base 10.

It is a strong prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 1995878785991 - 2²⁶ = 1995811677127 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1995878785997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 997939392995 + 997939392996.

It is an arithmetic number, because the mean of its divisors is an integer number (997939392996).

Almost surely, 2^{1995878785991} is an apocalyptic number.

1995878785991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1995878785991 is an equidigital number, since it uses as much as digits as its factorization.

1995878785991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4115059200, while the sum is 86.

The spelling of 1995878785991 in words is "one trillion, nine hundred ninety-five billion, eight hundred seventy-eight million, seven hundred eighty-five thousand, nine hundred ninety-one".