55681591 has 12 divisors (see below), whose sum is σ = 64980912. Its totient is φ = 47712672.

The previous prime is 55681583. The next prime is 55681631. The reversal of 55681591 is 19518655.

55681591 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 55681591 - 2³ = 55681583 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 (55681501) 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 11 ways as a sum of consecutive naturals, for example, 15151 + ... + 18463.

It is an arithmetic number, because the mean of its divisors is an integer number (5415076).

Almost surely, 2^55681591 is an apocalyptic number.

55681591 is a deficient number, since it is larger than the sum of its proper divisors (9299321).

55681591 is an frugal number, since it uses more digits than its factorization.

55681591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3348 (or 3320 counting only the distinct ones).

The product of its digits is 54000, while the sum is 40.

The square root of 55681591 is about 7462.0098498997. The cubic root of 55681591 is about 381.8597453912.

The spelling of 55681591 in words is "fifty-five million, six hundred eighty-one thousand, five hundred ninety-one".