191047561 has 4 divisors (see below), whose sum is σ = 191116800. Its totient is φ = 190978324.

The previous prime is 191047553. The next prime is 191047579. The reversal of 191047561 is 165740191.

191047561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 191047561 - 2³ = 191047553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191047501) 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, 30301 + ... + 36058.

It is an arithmetic number, because the mean of its divisors is an integer number (47779200).

Almost surely, 2^191047561 is an apocalyptic number.

It is an amenable number.

191047561 is a deficient number, since it is larger than the sum of its proper divisors (69239).

191047561 is an equidigital number, since it uses as much as digits as its factorization.

191047561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69238.

The product of its (nonzero) digits is 7560, while the sum is 34.

The square root of 191047561 is about 13821.9955505708. The cubic root of 191047561 is about 575.9443195035.

The spelling of 191047561 in words is "one hundred ninety-one million, forty-seven thousand, five hundred sixty-one".