981191291 has 2 divisors, whose sum is σ = 981191292. Its totient is φ = 981191290.

The previous prime is 981191221. The next prime is 981191327. The reversal of 981191291 is 192191189.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 981191291 - 2²⁶ = 914082427 is a prime.

It is not a weakly prime, because it can be changed into another prime (981191221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490595645 + 490595646.

It is an arithmetic number, because the mean of its divisors is an integer number (490595646).

Almost surely, 2^981191291 is an apocalyptic number.

981191291 is a deficient number, since it is larger than the sum of its proper divisors (1).

981191291 is an equidigital number, since it uses as much as digits as its factorization.

981191291 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 41.

The square root of 981191291 is about 31323.9731036789. The cubic root of 981191291 is about 993.6907068719.

The spelling of 981191291 in words is "nine hundred eighty-one million, one hundred ninety-one thousand, two hundred ninety-one".