11655506556661 has 4 divisors (see below), whose sum is σ = 12715098061824. Its totient is φ = 10595915051500.

The previous prime is 11655506556619. The next prime is 11655506556691. The reversal of 11655506556661 is 16665560555611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11655506556661 - 2²³ = 11655498168053 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11655506556596 and 11655506556605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11655506556691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 529795752565 + ... + 529795752586.

It is an arithmetic number, because the mean of its divisors is an integer number (3178774515456).

Almost surely, 2^{11655506556661} is an apocalyptic number.

11655506556661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11655506556661 is a deficient number, since it is larger than the sum of its proper divisors (1059591505163).

11655506556661 is a wasteful number, since it uses less digits than its factorization.

11655506556661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059591505162.

The product of its (nonzero) digits is 24300000, while the sum is 58.

The spelling of 11655506556661 in words is "eleven trillion, six hundred fifty-five billion, five hundred six million, five hundred fifty-six thousand, six hundred sixty-one".