1660663 has 2 divisors, whose sum is σ = 1660664. Its totient is φ = 1660662.

The previous prime is 1660661. The next prime is 1660667. The reversal of 1660663 is 3660661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1660663 - 2¹ = 1660661 is a prime.

Together with 1660661, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1660661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830331 + 830332.

It is an arithmetic number, because the mean of its divisors is an integer number (830332).

2^1660663 is an apocalyptic number.

1660663 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660663 is an equidigital number, since it uses as much as digits as its factorization.

1660663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 1660663 is about 1288.6671408863. The cubic root of 1660663 is about 118.4205761887.

The spelling of 1660663 in words is "one million, six hundred sixty thousand, six hundred sixty-three".