1663983 has 10 divisors (see below), whose sum is σ = 2485824. Its totient is φ = 1109268.

The previous prime is 1663973. The next prime is 1663997. The reversal of 1663983 is 3893661.

It is a happy number.

1663983 is a `hidden beast` number, since 16 + 639 + 8 + 3 = 666.

It is not a de Polignac number, because 1663983 - 2⁴ = 1663967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663913) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 10191 + ... + 10352.

2^1663983 is an apocalyptic number.

1663983 is a deficient number, since it is larger than the sum of its proper divisors (821841).

1663983 is an equidigital number, since it uses as much as digits as its factorization.

1663983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20555 (or 20546 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 1663983 is about 1289.9546503657. The cubic root of 1663983 is about 118.4994391898.

The spelling of 1663983 in words is "one million, six hundred sixty-three thousand, nine hundred eighty-three".