191296561 has 3 divisors (see below), whose sum is σ = 191310393. Its totient is φ = 191282730.

The previous prime is 191296559. The next prime is 191296577. The reversal of 191296561 is 165692191.

The square root of 191296561 is 13831.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 191296561 - 2¹ = 191296559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191296361) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 6916 + ... + 20746.

It is an arithmetic number, because the mean of its divisors is an integer number (63770131).

Almost surely, 2^191296561 is an apocalyptic number.

191296561 is the 13831-st square number.

191296561 is the 6916-th centered octagonal number.

It is an amenable number.

191296561 is a deficient number, since it is larger than the sum of its proper divisors (13832).

191296561 is an frugal number, since it uses more digits than its factorization.

191296561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27662 (or 13831 counting only the distinct ones).

The product of its digits is 29160, while the sum is 40.

The cubic root of 191296561 is about 576.1944280381.

The spelling of 191296561 in words is "one hundred ninety-one million, two hundred ninety-six thousand, five hundred sixty-one".