1663506 has 24 divisors (see below), whose sum is σ = 3882060. Its totient is φ = 511776.

The previous prime is 1663481. The next prime is 1663513. The reversal of 1663506 is 6053661.

It can be written as a sum of positive squares in 2 ways, for example, as 1418481 + 245025 = 1191^2 + 495^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1663506.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3321 + ... + 3788.

2^1663506 is an apocalyptic number.

1663506 is an abundant number, since it is smaller than the sum of its proper divisors (2218554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1663506 is a wasteful number, since it uses less digits than its factorization.

1663506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7130 (or 7127 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 1663506 is about 1289.7697468928. The cubic root of 1663506 is about 118.4881150287.

The spelling of 1663506 in words is "one million, six hundred sixty-three thousand, five hundred six".