55811320 has 16 divisors (see below), whose sum is σ = 125575560. Its totient is φ = 22324512.

The previous prime is 55811309. The next prime is 55811321. The reversal of 55811320 is 2311855.

It is a happy number.

It is a super-2 number, since 2×55811320² = 6229806880284800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55811321) 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, 697602 + ... + 697681.

Almost surely, 2^55811320 is an apocalyptic number.

It is an amenable number.

55811320 is an abundant number, since it is smaller than the sum of its proper divisors (69764240).

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

55811320 is a wasteful number, since it uses less digits than its factorization.

55811320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1395294 (or 1395290 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 55811320 is about 7470.6974239357. The cubic root of 55811320 is about 382.1560722963.

The spelling of 55811320 in words is "fifty-five million, eight hundred eleven thousand, three hundred twenty".