663521364 has 72 divisors (see below), whose sum is σ = 1834953120. Its totient is φ = 200491200.

The previous prime is 663521359. The next prime is 663521387. The reversal of 663521364 is 463125366.

663521364 is a `hidden beast` number, since 6 + 635 + 2 + 13 + 6 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 147874 + ... + 152294.

It is an arithmetic number, because the mean of its divisors is an integer number (25485460).

Almost surely, 2^663521364 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663521364, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (917476560).

663521364 is an abundant number, since it is smaller than the sum of its proper divisors (1171431756).

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

663521364 is a wasteful number, since it uses less digits than its factorization.

663521364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4821 (or 4816 counting only the distinct ones).

The product of its digits is 77760, while the sum is 36.

The square root of 663521364 is about 25758.9084396059. The cubic root of 663521364 is about 872.2044610054.

The spelling of 663521364 in words is "six hundred sixty-three million, five hundred twenty-one thousand, three hundred sixty-four".