55565551 has 8 divisors (see below), whose sum is σ = 56624400. Its totient is φ = 54510720.

The previous prime is 55565533. The next prime is 55565563. The reversal of 55565551 is 15556555.

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 55565551 - 2¹¹ = 55563503 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55565551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55565501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51445 + ... + 52513.

It is an arithmetic number, because the mean of its divisors is an integer number (7078050).

Almost surely, 2^55565551 is an apocalyptic number.

55565551 is a deficient number, since it is larger than the sum of its proper divisors (1058849).

55565551 is a wasteful number, since it uses less digits than its factorization.

55565551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2009.

The product of its digits is 93750, while the sum is 37.

The square root of 55565551 is about 7454.2304096399. The cubic root of 55565551 is about 381.5942966674.

The spelling of 55565551 in words is "fifty-five million, five hundred sixty-five thousand, five hundred fifty-one".