13291961553666 has 96 divisors (see below), whose sum is σ = 29921719464000. Its totient is φ = 4422376284480.

The previous prime is 13291961553643. The next prime is 13291961553709. The reversal of 13291961553666 is 66635516919231.

It is a super-3 number, since 3×13291961553666³ (a number of 40 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1213983160 + ... + 1213994108.

It is an arithmetic number, because the mean of its divisors is an integer number (311684577750).

Almost surely, 2^{13291961553666} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13291961553666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14960859732000).

13291961553666 is an abundant number, since it is smaller than the sum of its proper divisors (16629757910334).

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

13291961553666 is a wasteful number, since it uses less digits than its factorization.

13291961553666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15406 (or 15394 counting only the distinct ones).

The product of its digits is 47239200, while the sum is 63.

The spelling of 13291961553666 in words is "thirteen trillion, two hundred ninety-one billion, nine hundred sixty-one million, five hundred fifty-three thousand, six hundred sixty-six".