55181791 has 6 divisors (see below), whose sum is σ = 64191120. Its totient is φ = 47298636.

The previous prime is 55181773. The next prime is 55181831. The reversal of 55181791 is 19718155.

55181791 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 55181791 - 2¹⁵ = 55149023 is a prime.

It is a super-4 number, since 4×55181791⁴ (a number of 32 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55181791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55181701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 563031 + ... + 563128.

It is an arithmetic number, because the mean of its divisors is an integer number (10698520).

Almost surely, 2^55181791 is an apocalyptic number.

55181791 is a deficient number, since it is larger than the sum of its proper divisors (9009329).

55181791 is a wasteful number, since it uses less digits than its factorization.

55181791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1126173 (or 1126166 counting only the distinct ones).

The product of its digits is 12600, while the sum is 37.

The square root of 55181791 is about 7428.4447228205. Note that the first 3 decimals coincide. The cubic root of 55181791 is about 380.7137807612.

The spelling of 55181791 in words is "fifty-five million, one hundred eighty-one thousand, seven hundred ninety-one".