55509591 has 8 divisors (see below), whose sum is σ = 74255104. Its totient is φ = 36885240.

The previous prime is 55509589. The next prime is 55509593. The reversal of 55509591 is 19590555.

It is a happy number.

55509591 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (55509589) and next prime (55509593).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 55509591 - 2¹ = 55509589 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 (55509593) 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 7 ways as a sum of consecutive naturals, for example, 29215 + ... + 31056.

It is an arithmetic number, because the mean of its divisors is an integer number (9281888).

Almost surely, 2^55509591 is an apocalyptic number.

55509591 is a deficient number, since it is larger than the sum of its proper divisors (18745513).

55509591 is a wasteful number, since it uses less digits than its factorization.

55509591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60581.

The product of its (nonzero) digits is 50625, while the sum is 39.

The square root of 55509591 is about 7450.4758908408. The cubic root of 55509591 is about 381.4661525865.

The spelling of 55509591 in words is "fifty-five million, five hundred nine thousand, five hundred ninety-one".