1666040 has 16 divisors (see below), whose sum is σ = 3748680. Its totient is φ = 666400.

The previous prime is 1666039. The next prime is 1666043. The reversal of 1666040 is 406661.

It is a junction number, because it is equal to n+sod(n) for n = 1665997 and 1666015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666043) 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 3 ways as a sum of consecutive naturals, for example, 20786 + ... + 20865.

2^1666040 is an apocalyptic number.

1666040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666040 is an abundant number, since it is smaller than the sum of its proper divisors (2082640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1666040 is a wasteful number, since it uses less digits than its factorization.

1666040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41662 (or 41658 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 1666040 is about 1290.7517189607. The cubic root of 1666040 is about 118.5482483770.

The spelling of 1666040 in words is "one million, six hundred sixty-six thousand, forty".