663743907540 has 288 divisors, whose sum is σ = 2335427168256. Its totient is φ = 149445354240.

The previous prime is 663743907493. The next prime is 663743907551. The reversal of 663743907540 is 45709347366.

It is a happy number.

663743907540 is a `hidden beast` number, since 6 + 6 + 3 + 7 + 4 + 3 + 90 + 7 + 540 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 132666679 + ... + 132671681.

It is an arithmetic number, because the mean of its divisors is an integer number (8109122112).

Almost surely, 2^663743907540 is an apocalyptic number.

663743907540 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 663743907540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1167713584128).

663743907540 is an abundant number, since it is smaller than the sum of its proper divisors (1671683260716).

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

663743907540 is a wasteful number, since it uses less digits than its factorization.

663743907540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6579 (or 6574 counting only the distinct ones).

The product of its (nonzero) digits is 11430720, while the sum is 54.

The spelling of 663743907540 in words is "six hundred sixty-three billion, seven hundred forty-three million, nine hundred seven thousand, five hundred forty".