33130111991 has 2 divisors, whose sum is σ = 33130111992. Its totient is φ = 33130111990.

The previous prime is 33130111979. The next prime is 33130111997. The reversal of 33130111991 is 19911103133.

It is a strong prime.

It is an emirp because it is prime and its reverse (19911103133) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 33130111991 - 2¹⁸ = 33129849847 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33130111997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16565055995 + 16565055996.

It is an arithmetic number, because the mean of its divisors is an integer number (16565055996).

Almost surely, 2^33130111991 is an apocalyptic number.

33130111991 is a deficient number, since it is larger than the sum of its proper divisors (1).

33130111991 is an equidigital number, since it uses as much as digits as its factorization.

33130111991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2187, while the sum is 32.

The spelling of 33130111991 in words is "thirty-three billion, one hundred thirty million, one hundred eleven thousand, nine hundred ninety-one".