55601611555561 has 4 divisors (see below), whose sum is σ = 55601911081872. Its totient is φ = 55601312029252.

The previous prime is 55601611555547. The next prime is 55601611555661. The reversal of 55601611555561 is 16555511610655.

It is a happy number.

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 55601611555561 - 2¹⁹ = 55601611031273 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 55601611555499 and 55601611555508.

It is not an unprimeable number, because it can be changed into a prime (55601611555541) 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, 149484535 + ... + 149856028.

It is an arithmetic number, because the mean of its divisors is an integer number (13900477770468).

Almost surely, 2^{55601611555561} is an apocalyptic number.

It is an amenable number.

55601611555561 is a deficient number, since it is larger than the sum of its proper divisors (299526311).

55601611555561 is a wasteful number, since it uses less digits than its factorization.

55601611555561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299526310.

The product of its (nonzero) digits is 3375000, while the sum is 52.

The spelling of 55601611555561 in words is "fifty-five trillion, six hundred one billion, six hundred eleven million, five hundred fifty-five thousand, five hundred sixty-one".