55645638 has 8 divisors (see below), whose sum is σ = 111291288. Its totient is φ = 18548544.

The previous prime is 55645633. The next prime is 55645649. The reversal of 55645638 is 83654655.

It is a happy number.

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

55645638 is an admirable number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 55645638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55645633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4637131 + ... + 4637142.

It is an arithmetic number, because the mean of its divisors is an integer number (13911411).

Almost surely, 2^55645638 is an apocalyptic number.

55645638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55645638 is a wasteful number, since it uses less digits than its factorization.

55645638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9274278.

The product of its digits is 432000, while the sum is 42.

The square root of 55645638 is about 7459.6003914419. The cubic root of 55645638 is about 381.7775401289. Note that the first 3 decimals are identical.

The spelling of 55645638 in words is "fifty-five million, six hundred forty-five thousand, six hundred thirty-eight".