55643140 has 48 divisors (see below), whose sum is σ = 137862144. Its totient is φ = 18460800.

The previous prime is 55643129. The next prime is 55643143. The reversal of 55643140 is 4134655.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 55643099 and 55643108.

It is not an unprimeable number, because it can be changed into a prime (55643143) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2071 + ... + 10750.

It is an arithmetic number, because the mean of its divisors is an integer number (2872128).

Almost surely, 2^55643140 is an apocalyptic number.

It is an amenable number.

55643140 is an abundant number, since it is smaller than the sum of its proper divisors (82219004).

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

55643140 is a wasteful number, since it uses less digits than its factorization.

55643140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12868 (or 12866 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 55643140 is about 7459.4329543203. The cubic root of 55643140 is about 381.7718272249.

Adding to 55643140 its reverse (4134655), we get a palindrome (59777795).

The spelling of 55643140 in words is "fifty-five million, six hundred forty-three thousand, one hundred forty".