191132153981 has 2 divisors, whose sum is σ = 191132153982. Its totient is φ = 191132153980.

The previous prime is 191132153951. The next prime is 191132154089. The reversal of 191132153981 is 189351231191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 175679177881 + 15452976100 = 419141^2 + 124310^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191132153981 is a prime.

It is a super-2 number, since 2×191132153981² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191132153911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95566076990 + 95566076991.

It is an arithmetic number, because the mean of its divisors is an integer number (95566076991).

Almost surely, 2^191132153981 is an apocalyptic number.

It is an amenable number.

191132153981 is a deficient number, since it is larger than the sum of its proper divisors (1).

191132153981 is an equidigital number, since it uses as much as digits as its factorization.

191132153981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58320, while the sum is 44.

The spelling of 191132153981 in words is "one hundred ninety-one billion, one hundred thirty-two million, one hundred fifty-three thousand, nine hundred eighty-one".