1660191 has 8 divisors (see below), whose sum is σ = 2383920. Its totient is φ = 1021632.

The previous prime is 1660189. The next prime is 1660199. The reversal of 1660191 is 1910661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1660191 - 2¹ = 1660189 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660199) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21246 + ... + 21323.

It is an arithmetic number, because the mean of its divisors is an integer number (297990).

2^1660191 is an apocalyptic number.

1660191 is a deficient number, since it is larger than the sum of its proper divisors (723729).

1660191 is a wasteful number, since it uses less digits than its factorization.

1660191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42585.

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 1660191 is about 1288.4839929157. The cubic root of 1660191 is about 118.4093558090.

The spelling of 1660191 in words is "one million, six hundred sixty thousand, one hundred ninety-one".