5655721061561 has 4 divisors (see below), whose sum is σ = 5689587654912. Its totient is φ = 5621854468212.

The previous prime is 5655721061509. The next prime is 5655721061567. The reversal of 5655721061561 is 1651601275565.

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 5655721061561 - 2¹⁰ = 5655721060537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5655721061567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16933296425 + ... + 16933296758.

It is an arithmetic number, because the mean of its divisors is an integer number (1422396913728).

Almost surely, 2^{5655721061561} is an apocalyptic number.

It is an amenable number.

5655721061561 is a deficient number, since it is larger than the sum of its proper divisors (33866593351).

5655721061561 is a wasteful number, since it uses less digits than its factorization.

5655721061561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33866593350.

The product of its (nonzero) digits is 1890000, while the sum is 50.

The spelling of 5655721061561 in words is "five trillion, six hundred fifty-five billion, seven hundred twenty-one million, sixty-one thousand, five hundred sixty-one".