663801863 has 4 divisors (see below), whose sum is σ = 664209000. Its totient is φ = 663394728.

The previous prime is 663801829. The next prime is 663801869. The reversal of 663801863 is 368108366.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 663801863 - 2¹⁶ = 663736327 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 663801863.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663801869) 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, 201113 + ... + 204386.

It is an arithmetic number, because the mean of its divisors is an integer number (166052250).

Almost surely, 2^663801863 is an apocalyptic number.

663801863 is a deficient number, since it is larger than the sum of its proper divisors (407137).

663801863 is a wasteful number, since it uses less digits than its factorization.

663801863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407136.

The product of its (nonzero) digits is 124416, while the sum is 41.

The square root of 663801863 is about 25764.3525631831. The cubic root of 663801863 is about 872.3273497951.

The spelling of 663801863 in words is "six hundred sixty-three million, eight hundred one thousand, eight hundred sixty-three".