55809917 has 4 divisors (see below), whose sum is σ = 55830336. Its totient is φ = 55789500.

The previous prime is 55809913. The next prime is 55809931. The reversal of 55809917 is 71990855.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55809917 - 2² = 55809913 is a prime.

It is a super-2 number, since 2×55809917² = 6229493671093778, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55809911) 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, 5333 + ... + 11834.

It is an arithmetic number, because the mean of its divisors is an integer number (13957584).

Almost surely, 2^55809917 is an apocalyptic number.

It is an amenable number.

55809917 is a deficient number, since it is larger than the sum of its proper divisors (20419).

55809917 is a wasteful number, since it uses less digits than its factorization.

55809917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20418.

The product of its (nonzero) digits is 113400, while the sum is 44.

The square root of 55809917 is about 7470.6035231432. The cubic root of 55809917 is about 382.1528700220.

The spelling of 55809917 in words is "fifty-five million, eight hundred nine thousand, nine hundred seventeen".