661887714956832 has 1152 divisors, whose sum is σ = 2413566743777280. Its totient is φ = 173754394030080.

The previous prime is 661887714956813. The next prime is 661887714956849. The reversal of 661887714956832 is 238659417788166.

661887714956832 is a `hidden beast` number, since 6 + 6 + 1 + 8 + 8 + 7 + 7 + 1 + 49 + 568 + 3 + 2 = 666.

661887714956832 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 324613885669 + ... + 324613887707.

It is an arithmetic number, because the mean of its divisors is an integer number (2095110020640).

Almost surely, 2^{661887714956832} 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 661887714956832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1206783371888640).

661887714956832 is an abundant number, since it is smaller than the sum of its proper divisors (1751679028820448).

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

661887714956832 is a wasteful number, since it uses less digits than its factorization.

661887714956832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3988 (or 3968 counting only the distinct ones).

The product of its digits is 5852528640, while the sum is 81.

The spelling of 661887714956832 in words is "six hundred sixty-one trillion, eight hundred eighty-seven billion, seven hundred fourteen million, nine hundred fifty-six thousand, eight hundred thirty-two".