1606663 has 2 divisors, whose sum is σ = 1606664. Its totient is φ = 1606662.

The previous prime is 1606643. The next prime is 1606669. The reversal of 1606663 is 3666061.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1606663 - 2⁹ = 1606151 is a prime.

It is an Ulam number.

1606663 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1606669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 803331 + 803332.

It is an arithmetic number, because the mean of its divisors is an integer number (803332).

2^1606663 is an apocalyptic number.

1606663 is a deficient number, since it is larger than the sum of its proper divisors (1).

1606663 is an equidigital number, since it uses as much as digits as its factorization.

1606663 is an odious number, because the sum of its binary digits is odd.

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

The square root of 1606663 is about 1267.5421097541. The cubic root of 1606663 is about 117.1228407628.

It can be divided in two parts, 16066 and 63, that added together give a square (16129 = 127²).

The spelling of 1606663 in words is "one million, six hundred six thousand, six hundred sixty-three".