55131887 has 4 divisors (see below), whose sum is σ = 56621976. Its totient is φ = 53641800.

The previous prime is 55131859. The next prime is 55131889. The reversal of 55131887 is 78813155.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 55131887 - 2⁶ = 55131823 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 55131887.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55131889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 744989 + ... + 745062.

It is an arithmetic number, because the mean of its divisors is an integer number (14155494).

Almost surely, 2^55131887 is an apocalyptic number.

55131887 is a deficient number, since it is larger than the sum of its proper divisors (1490089).

55131887 is a wasteful number, since it uses less digits than its factorization.

55131887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1490088.

The product of its digits is 33600, while the sum is 38.

The square root of 55131887 is about 7425.0849826786. The cubic root of 55131887 is about 380.5989791791.

The spelling of 55131887 in words is "fifty-five million, one hundred thirty-one thousand, eight hundred eighty-seven".