1663520 has 48 divisors (see below), whose sum is σ = 4050648. Its totient is φ = 645120.

The previous prime is 1663517. The next prime is 1663523. The reversal of 1663520 is 253661.

It is an interprime number because it is at equal distance from previous prime (1663517) and next prime (1663523).

It can be written as a sum of positive squares in 4 ways, for example, as 1628176 + 35344 = 1276^2 + 188^2 .

It is not an unprimeable number, because it can be changed into a prime (1663523) 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 in 7 ways as a sum of consecutive naturals, for example, 5780 + ... + 6060.

2^1663520 is an apocalyptic number.

1663520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1663520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2025324).

1663520 is an abundant number, since it is smaller than the sum of its proper divisors (2387128).

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

1663520 is a wasteful number, since it uses less digits than its factorization.

1663520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333 (or 325 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 1663520 is about 1289.7751742067. The cubic root of 1663520 is about 118.4884474249.

It can be divided in two parts, 16 and 63520, that added together give a palindrome (63536).

The spelling of 1663520 in words is "one million, six hundred sixty-three thousand, five hundred twenty".