11661556550611 has 8 divisors (see below), whose sum is σ = 12845209688064. Its totient is φ = 10498488685320.

The previous prime is 11661556550531. The next prime is 11661556550717. The reversal of 11661556550611 is 11605565516611.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11661556550611 - 2³⁹ = 11111800736723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11661556550311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5146316851 + ... + 5146319116.

It is an arithmetic number, because the mean of its divisors is an integer number (1605651211008).

Almost surely, 2^{11661556550611} is an apocalyptic number.

11661556550611 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11661556550611 is a deficient number, since it is larger than the sum of its proper divisors (1183653137453).

11661556550611 is a wasteful number, since it uses less digits than its factorization.

11661556550611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10292636081.

The product of its (nonzero) digits is 810000, while the sum is 49.

The spelling of 11661556550611 in words is "eleven trillion, six hundred sixty-one billion, five hundred fifty-six million, five hundred fifty thousand, six hundred eleven".