55209599 has 4 divisors (see below), whose sum is σ = 55349064. Its totient is φ = 55070136.

The previous prime is 55209593. The next prime is 55209607. The reversal of 55209599 is 99590255.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55209599 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 (55209593) 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, 69137 + ... + 69930.

It is an arithmetic number, because the mean of its divisors is an integer number (13837266).

Almost surely, 2^55209599 is an apocalyptic number.

55209599 is a deficient number, since it is larger than the sum of its proper divisors (139465).

55209599 is a wasteful number, since it uses less digits than its factorization.

55209599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139464.

The product of its (nonzero) digits is 182250, while the sum is 44.

The square root of 55209599 is about 7430.3162113062. The cubic root of 55209599 is about 380.7777216057. Note that the first 4 decimals are identical.

The spelling of 55209599 in words is "fifty-five million, two hundred nine thousand, five hundred ninety-nine".