55163640 has 128 divisors (see below), whose sum is σ = 200309760. Its totient is φ = 11864064.

The previous prime is 55163621. The next prime is 55163651. The reversal of 55163640 is 4636155.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 55163598 and 55163607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12349 + ... + 16211.

It is an arithmetic number, because the mean of its divisors is an integer number (1564920).

Almost surely, 2^55163640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55163640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100154880).

55163640 is an abundant number, since it is smaller than the sum of its proper divisors (145146120).

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

55163640 is a wasteful number, since it uses less digits than its factorization.

55163640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3901 (or 3897 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 55163640 is about 7427.2228995769. Note that the first 3 decimals coincide. The cubic root of 55163640 is about 380.6720333325.

Adding to 55163640 its reverse (4636155), we get a palindrome (59799795).

The spelling of 55163640 in words is "fifty-five million, one hundred sixty-three thousand, six hundred forty".