55550505661 has 16 divisors (see below), whose sum is σ = 64853718400. Its totient is φ = 47561955840.

The previous prime is 55550505649. The next prime is 55550505667. The reversal of 55550505661 is 16650505555.

It is not a de Polignac number, because 55550505661 - 2²⁵ = 55516951229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55550505667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 221821 + ... + 400381.

It is an arithmetic number, because the mean of its divisors is an integer number (4053357400).

Almost surely, 2^55550505661 is an apocalyptic number.

It is an amenable number.

55550505661 is a deficient number, since it is larger than the sum of its proper divisors (9303212739).

55550505661 is an equidigital number, since it uses as much as digits as its factorization.

55550505661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179489 (or 179475 counting only the distinct ones).

The product of its (nonzero) digits is 562500, while the sum is 43.

The spelling of 55550505661 in words is "fifty-five billion, five hundred fifty million, five hundred five thousand, six hundred sixty-one".