17661220864 has 192 divisors, whose sum is σ = 43589145600. Its totient is φ = 6986563584.

The previous prime is 17661220859. The next prime is 17661220901. The reversal of 17661220864 is 46802216671.

It is a self number, because there is not a number n which added to its sum of digits gives 17661220864.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9561189 + ... + 9563035.

It is an arithmetic number, because the mean of its divisors is an integer number (227026800).

Almost surely, 2^17661220864 is an apocalyptic number.

17661220864 is a gapful number since it is divisible by the number (14) 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 17661220864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21794572800).

17661220864 is an abundant number, since it is smaller than the sum of its proper divisors (25927924736).

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

17661220864 is a wasteful number, since it uses less digits than its factorization.

17661220864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1928 (or 1908 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 17661220864 in words is "seventeen billion, six hundred sixty-one million, two hundred twenty thousand, eight hundred sixty-four".