1666516 has 6 divisors (see below), whose sum is σ = 2916410. Its totient is φ = 833256.

The previous prime is 1666507. The next prime is 1666519. The reversal of 1666516 is 6156661.

It can be written as a sum of positive squares in only one way, i.e., 1020100 + 646416 = 1010^2 + 804^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 208311 + ... + 208318.

2^1666516 is an apocalyptic number.

It is an amenable number.

1666516 is a deficient number, since it is larger than the sum of its proper divisors (1249894).

1666516 is a wasteful number, since it uses less digits than its factorization.

1666516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416633 (or 416631 counting only the distinct ones).

The product of its digits is 6480, while the sum is 31.

The square root of 1666516 is about 1290.9360944679. The cubic root of 1666516 is about 118.5595373403.

The spelling of 1666516 in words is "one million, six hundred sixty-six thousand, five hundred sixteen".