1663540 has 12 divisors (see below), whose sum is σ = 3493476. Its totient is φ = 665408.

The previous prime is 1663537. The next prime is 1663547. The reversal of 1663540 is 453661.

It can be written as a sum of positive squares in 2 ways, for example, as 753424 + 910116 = 868^2 + 954^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663547) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41569 + ... + 41608.

It is an arithmetic number, because the mean of its divisors is an integer number (291123).

2^1663540 is an apocalyptic number.

1663540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1663540 is an abundant number, since it is smaller than the sum of its proper divisors (1829936).

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

1663540 is a wasteful number, since it uses less digits than its factorization.

1663540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83186 (or 83184 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 1663540 is about 1289.7829274727. The cubic root of 1663540 is about 118.4889222733.

The spelling of 1663540 in words is "one million, six hundred sixty-three thousand, five hundred forty".