663873 has 16 divisors (see below), whose sum is σ = 1024896. Its totient is φ = 374400.

The previous prime is 663869. The next prime is 663881. The reversal of 663873 is 378366.

It is a happy number.

It is not a de Polignac number, because 663873 - 2² = 663869 is a prime.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (663823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1965 + ... + 2277.

It is an arithmetic number, because the mean of its divisors is an integer number (64056).

2⁶⁶³⁸⁷³ is an apocalyptic number.

It is an amenable number.

663873 is a deficient number, since it is larger than the sum of its proper divisors (361023).

663873 is a wasteful number, since it uses less digits than its factorization.

663873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424.

The product of its digits is 18144, while the sum is 33.

The square root of 663873 is about 814.7840204619. The cubic root of 663873 is about 87.2358509964.

The spelling of 663873 in words is "six hundred sixty-three thousand, eight hundred seventy-three".