1668994 has 4 divisors (see below), whose sum is σ = 2503494. Its totient is φ = 834496.

The previous prime is 1668983. The next prime is 1669027. The reversal of 1668994 is 4998661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4998661 = 191 ⋅26171.

It can be written as a sum of positive squares in only one way, i.e., 1380625 + 288369 = 1175^2 + 537^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1668994.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 417247 + ... + 417250.

2^1668994 is an apocalyptic number.

1668994 is a deficient number, since it is larger than the sum of its proper divisors (834500).

1668994 is an equidigital number, since it uses as much as digits as its factorization.

1668994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834499.

The product of its digits is 93312, while the sum is 43.

The square root of 1668994 is about 1291.8955066103. The cubic root of 1668994 is about 118.6182716575.

It can be divided in two parts, 1668 and 994, that added together give a palindrome (2662).

The spelling of 1668994 in words is "one million, six hundred sixty-eight thousand, nine hundred ninety-four".