1662667 has 2 divisors, whose sum is σ = 1662668. Its totient is φ = 1662666.

The previous prime is 1662653. The next prime is 1662697. The reversal of 1662667 is 7662661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1662667 - 2¹⁵ = 1629899 is a prime.

It is not a weakly prime, because it can be changed into another prime (1662637) 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 as a sum of consecutive naturals, namely, 831333 + 831334.

It is an arithmetic number, because the mean of its divisors is an integer number (831334).

2^1662667 is an apocalyptic number.

1662667 is a deficient number, since it is larger than the sum of its proper divisors (1).

1662667 is an equidigital number, since it uses as much as digits as its factorization.

1662667 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 34.

The square root of 1662667 is about 1289.4444540189. Note that the first 4 decimals coincide. The cubic root of 1662667 is about 118.4681915967.

The spelling of 1662667 in words is "one million, six hundred sixty-two thousand, six hundred sixty-seven".