55091605 has 4 divisors (see below), whose sum is σ = 66109932. Its totient is φ = 44073280.

The previous prime is 55091593. The next prime is 55091609. The reversal of 55091605 is 50619055.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15665764 + 39425841 = 3958^2 + 6279^2 .

It is not a de Polignac number, because 55091605 - 2⁹ = 55091093 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 (55091609) 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 3 ways as a sum of consecutive naturals, for example, 5509156 + ... + 5509165.

It is an arithmetic number, because the mean of its divisors is an integer number (16527483).

Almost surely, 2^55091605 is an apocalyptic number.

It is an amenable number.

55091605 is a deficient number, since it is larger than the sum of its proper divisors (11018327).

55091605 is a wasteful number, since it uses less digits than its factorization.

55091605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11018326.

The product of its (nonzero) digits is 6750, while the sum is 31.

The square root of 55091605 is about 7422.3719254696. The cubic root of 55091605 is about 380.5062619734.

It can be divided in two parts, 55091 and 605, that added together give a square (55696 = 236²).

The spelling of 55091605 in words is "fifty-five million, ninety-one thousand, six hundred five".