660503191 has 4 divisors (see below), whose sum is σ = 660564000. Its totient is φ = 660442384.

The previous prime is 660503149. The next prime is 660503231. The reversal of 660503191 is 191305066.

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 a cyclic number.

It is not a de Polignac number, because 660503191 - 2⁹ = 660502679 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 (660503141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9166 + ... + 37483.

It is an arithmetic number, because the mean of its divisors is an integer number (165141000).

Almost surely, 2^660503191 is an apocalyptic number.

660503191 is a deficient number, since it is larger than the sum of its proper divisors (60809).

660503191 is a wasteful number, since it uses less digits than its factorization.

660503191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60808.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 660503191 is about 25700.2566329599. The cubic root of 660503191 is about 870.8799794025.

The spelling of 660503191 in words is "six hundred sixty million, five hundred three thousand, one hundred ninety-one".