981221180191 has 4 divisors (see below), whose sum is σ = 1121395634512. Its totient is φ = 841046725872.

The previous prime is 981221180153. The next prime is 981221180231. The reversal of 981221180191 is 191081122189.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 981221180191 - 2¹⁷ = 981221049119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981221183191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70087227150 + ... + 70087227163.

It is an arithmetic number, because the mean of its divisors is an integer number (280348908628).

Almost surely, 2^981221180191 is an apocalyptic number.

981221180191 is a deficient number, since it is larger than the sum of its proper divisors (140174454321).

981221180191 is a wasteful number, since it uses less digits than its factorization.

981221180191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140174454320.

The product of its (nonzero) digits is 20736, while the sum is 43.

The spelling of 981221180191 in words is "nine hundred eighty-one billion, two hundred twenty-one million, one hundred eighty thousand, one hundred ninety-one".