1666913 has 2 divisors, whose sum is σ = 1666914. Its totient is φ = 1666912.

The previous prime is 1666909. The next prime is 1666919. The reversal of 1666913 is 3196661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1014049 + 652864 = 1007^2 + 808^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666913 - 2² = 1666909 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1666913.

It is not a weakly prime, because it can be changed into another prime (1666919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833456 + 833457.

It is an arithmetic number, because the mean of its divisors is an integer number (833457).

2^1666913 is an apocalyptic number.

It is an amenable number.

1666913 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666913 is an equidigital number, since it uses as much as digits as its factorization.

1666913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832, while the sum is 32.

The square root of 1666913 is about 1291.0898497006. The cubic root of 1666913 is about 118.5689510711.

The spelling of 1666913 in words is "one million, six hundred sixty-six thousand, nine hundred thirteen".