663444540 has 192 divisors, whose sum is σ = 2289853440. Its totient is φ = 158112000.

The previous prime is 663444539. The next prime is 663444553. The reversal of 663444540 is 45444366.

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

It is a junction number, because it is equal to n+sod(n) for n = 663444495 and 663444504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 361425 + ... + 363255.

It is an arithmetic number, because the mean of its divisors is an integer number (11926320).

Almost surely, 2^663444540 is an apocalyptic number.

663444540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663444540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1144926720).

663444540 is an abundant number, since it is smaller than the sum of its proper divisors (1626408900).

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

663444540 is a wasteful number, since it uses less digits than its factorization.

663444540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1921 (or 1913 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 36.

The square root of 663444540 is about 25757.4171841821. The cubic root of 663444540 is about 872.1707977730.

The spelling of 663444540 in words is "six hundred sixty-three million, four hundred forty-four thousand, five hundred forty".