1662791 has 6 divisors (see below), whose sum is σ = 1800720. Its totient is φ = 1534728.

The previous prime is 1662781. The next prime is 1662803. The reversal of 1662791 is 1972661.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1662791 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 (1662701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4751 + ... + 5088.

It is an arithmetic number, because the mean of its divisors is an integer number (300120).

2^1662791 is an apocalyptic number.

1662791 is a deficient number, since it is larger than the sum of its proper divisors (137929).

1662791 is an equidigital number, since it uses as much as digits as its factorization.

1662791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9865 (or 9852 counting only the distinct ones).

The product of its digits is 4536, while the sum is 32.

The square root of 1662791 is about 1289.4925358450. The cubic root of 1662791 is about 118.4711366022.

The spelling of 1662791 in words is "one million, six hundred sixty-two thousand, seven hundred ninety-one".