1155321229991 has 2 divisors, whose sum is σ = 1155321229992. Its totient is φ = 1155321229990.

The previous prime is 1155321229961. The next prime is 1155321230047. The reversal of 1155321229991 is 1999221235511.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1155321229991 - 2¹⁰ = 1155321228967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1155321229961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 577660614995 + 577660614996.

It is an arithmetic number, because the mean of its divisors is an integer number (577660614996).

Almost surely, 2^{1155321229991} is an apocalyptic number.

1155321229991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1155321229991 is an equidigital number, since it uses as much as digits as its factorization.

1155321229991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 437400, while the sum is 50.

The spelling of 1155321229991 in words is "one trillion, one hundred fifty-five billion, three hundred twenty-one million, two hundred twenty-nine thousand, nine hundred ninety-one".