1666740 has 24 divisors (see below), whose sum is σ = 4667040. Its totient is φ = 444448.

The previous prime is 1666733. The next prime is 1666757. The reversal of 1666740 is 476661.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1666698 and 1666707.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13830 + ... + 13949.

It is an arithmetic number, because the mean of its divisors is an integer number (194460).

2^1666740 is an apocalyptic number.

1666740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666740 is an abundant number, since it is smaller than the sum of its proper divisors (3000300).

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

1666740 is a wasteful number, since it uses less digits than its factorization.

1666740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27791 (or 27789 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 1666740 is about 1291.0228503013. The cubic root of 1666740 is about 118.5648490498.

The spelling of 1666740 in words is "one million, six hundred sixty-six thousand, seven hundred forty".