663870 has 16 divisors (see below), whose sum is σ = 1593360. Its totient is φ = 177024.

The previous prime is 663869. The next prime is 663881. The reversal of 663870 is 78366.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 22129 = 663870 / (6 + 6 + 3 + 8 + 7 + 0).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11035 + ... + 11094.

It is an arithmetic number, because the mean of its divisors is an integer number (99585).

2⁶⁶³⁸⁷⁰ is an apocalyptic number.

663870 is an abundant number, since it is smaller than the sum of its proper divisors (929490).

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

663870 is a wasteful number, since it uses less digits than its factorization.

663870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22139.

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 663870 is about 814.7821794811. The cubic root of 663870 is about 87.2357195918.

The spelling of 663870 in words is "six hundred sixty-three thousand, eight hundred seventy".