55011840 has 320 divisors, whose sum is σ = 206236800. Its totient is φ = 12386304.

The previous prime is 55011839. The next prime is 55011841. The reversal of 55011840 is 4811055.

It is an interprime number because it is at equal distance from previous prime (55011839) and next prime (55011841).

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 55011840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55011841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1896946 + ... + 1896974.

It is an arithmetic number, because the mean of its divisors is an integer number (644490).

Almost surely, 2^55011840 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 55011840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103118400).

55011840 is an abundant number, since it is smaller than the sum of its proper divisors (151224960).

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

55011840 is a wasteful number, since it uses less digits than its factorization.

55011840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 55011840 is about 7416.9966967769. The cubic root of 55011840 is about 380.3225331831.

Adding to 55011840 its reverse (4811055), we get a palindrome (59822895).

The spelling of 55011840 in words is "fifty-five million, eleven thousand, eight hundred forty".