55478787 has 32 divisors (see below), whose sum is σ = 91972608. Its totient is φ = 28964736.

The previous prime is 55478779. The next prime is 55478861. The reversal of 55478787 is 78787455.

It is not a de Polignac number, because 55478787 - 2³ = 55478779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55478767) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27133 + ... + 29105.

It is an arithmetic number, because the mean of its divisors is an integer number (2874144).

Almost surely, 2^55478787 is an apocalyptic number.

55478787 is a deficient number, since it is larger than the sum of its proper divisors (36493821).

55478787 is a wasteful number, since it uses less digits than its factorization.

55478787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2099.

The product of its digits is 2195200, while the sum is 51.

The square root of 55478787 is about 7448.4083534672. The cubic root of 55478787 is about 381.3955770491.

It can be divided in two parts, 55478 and 787, that added together give a palindrome (56265).

The spelling of 55478787 in words is "fifty-five million, four hundred seventy-eight thousand, seven hundred eighty-seven".