56540191 has 4 divisors (see below), whose sum is σ = 57068712. Its totient is φ = 56011672.

The previous prime is 56540173. The next prime is 56540203. The reversal of 56540191 is 19104565.

56540191 = T₆₁₃₈ + T₆₁₃₉ + T₆₁₄₀.

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 56540191 - 2¹⁹ = 56015903 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56540101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264100 + ... + 264313.

It is an arithmetic number, because the mean of its divisors is an integer number (14267178).

Almost surely, 2^56540191 is an apocalyptic number.

56540191 is the 6140-th centered triangular number.

56540191 is a deficient number, since it is larger than the sum of its proper divisors (528521).

56540191 is a wasteful number, since it uses less digits than its factorization.

56540191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528520.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 56540191 is about 7519.3211794683. The cubic root of 56540191 is about 383.8124785186.

The spelling of 56540191 in words is "fifty-six million, five hundred forty thousand, one hundred ninety-one".