55805040 has 120 divisors (see below), whose sum is σ = 188894160. Its totient is φ = 14764032.

The previous prime is 55805039. The next prime is 55805051. The reversal of 55805040 is 4050855.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×55805040² = 6228404978803200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 55804995 and 55805013.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 128664 + ... + 129096.

It is an arithmetic number, because the mean of its divisors is an integer number (1574118).

Almost surely, 2^55805040 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 55805040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94447080).

55805040 is an abundant number, since it is smaller than the sum of its proper divisors (133089120).

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

55805040 is a wasteful number, since it uses less digits than its factorization.

55805040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631 (or 622 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 27.

The square root of 55805040 is about 7470.2771032941. The cubic root of 55805040 is about 382.1417381065.

Adding to 55805040 its reverse (4050855), we get a palindrome (59855895).

The spelling of 55805040 in words is "fifty-five million, eight hundred five thousand, forty".