11661066556640 has 96 divisors (see below), whose sum is σ = 27647503220736. Its totient is φ = 4647813857280.

The previous prime is 11661066556637. The next prime is 11661066556651. The reversal of 11661066556640 is 4665566016611.

11661066556640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77924129 + ... + 78073631.

It is an arithmetic number, because the mean of its divisors is an integer number (287994825216).

Almost surely, 2^{11661066556640} is an apocalyptic number.

11661066556640 is a gapful number since it is divisible by the number (10) 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 11661066556640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13823751610368).

11661066556640 is an abundant number, since it is smaller than the sum of its proper divisors (15986436664096).

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

11661066556640 is a wasteful number, since it uses less digits than its factorization.

11661066556640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151252 (or 151244 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 53.

The spelling of 11661066556640 in words is "eleven trillion, six hundred sixty-one billion, sixty-six million, five hundred fifty-six thousand, six hundred forty".