1966791 has 4 divisors (see below), whose sum is σ = 2622392. Its totient is φ = 1311192.

The previous prime is 1966787. The next prime is 1966793. The reversal of 1966791 is 1976691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1976691 = 3 ⋅658897.

It is not a de Polignac number, because 1966791 - 2² = 1966787 is a prime.

It is a D-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 (1966793) 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, 327796 + ... + 327801.

It is an arithmetic number, because the mean of its divisors is an integer number (655598).

2^1966791 is an apocalyptic number.

1966791 is a deficient number, since it is larger than the sum of its proper divisors (655601).

1966791 is an equidigital number, since it uses as much as digits as its factorization.

1966791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655600.

The product of its digits is 20412, while the sum is 39.

The square root of 1966791 is about 1402.4232599326. The cubic root of 1966791 is about 125.2908639935.

The spelling of 1966791 in words is "one million, nine hundred sixty-six thousand, seven hundred ninety-one".