191247598081 has 4 divisors (see below), whose sum is σ = 191248480192. Its totient is φ = 191246715972.

The previous prime is 191247598079. The next prime is 191247598097. The reversal of 191247598081 is 180895742191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 191247598081 - 2¹ = 191247598079 is a prime.

It is a super-2 number, since 2×191247598081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191247598051) 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, 134596 + ... + 632938.

It is an arithmetic number, because the mean of its divisors is an integer number (47812120048).

Almost surely, 2^191247598081 is an apocalyptic number.

It is an amenable number.

191247598081 is a deficient number, since it is larger than the sum of its proper divisors (882111).

191247598081 is an equidigital number, since it uses as much as digits as its factorization.

191247598081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 882110.

The product of its (nonzero) digits is 1451520, while the sum is 55.

The spelling of 191247598081 in words is "one hundred ninety-one billion, two hundred forty-seven million, five hundred ninety-eight thousand, eighty-one".