55136621 has 16 divisors (see below), whose sum is σ = 58206720. Its totient is φ = 52179120.

The previous prime is 55136597. The next prime is 55136639. The reversal of 55136621 is 12663155.

55136621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55136621 is a prime.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55136671) 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 15 ways as a sum of consecutive naturals, for example, 261206 + ... + 261416.

It is an arithmetic number, because the mean of its divisors is an integer number (3637920).

Almost surely, 2^55136621 is an apocalyptic number.

It is an amenable number.

55136621 is a deficient number, since it is larger than the sum of its proper divisors (3070099).

55136621 is a wasteful number, since it uses less digits than its factorization.

55136621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416.

The product of its digits is 5400, while the sum is 29.

The square root of 55136621 is about 7425.4037600658. The cubic root of 55136621 is about 380.6098724758.

Adding to 55136621 its reverse (12663155), we get a palindrome (67799776).

The spelling of 55136621 in words is "fifty-five million, one hundred thirty-six thousand, six hundred twenty-one".