55578220 has 12 divisors (see below), whose sum is σ = 116714304. Its totient is φ = 22231280.

The previous prime is 55578217. The next prime is 55578223. The reversal of 55578220 is 2287555.

It is an interprime number because it is at equal distance from previous prime (55578217) and next prime (55578223).

It is not an unprimeable number, because it can be changed into a prime (55578223) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1389436 + ... + 1389475.

It is an arithmetic number, because the mean of its divisors is an integer number (9726192).

Almost surely, 2^55578220 is an apocalyptic number.

It is an amenable number.

55578220 is an abundant number, since it is smaller than the sum of its proper divisors (61136084).

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

55578220 is a wasteful number, since it uses less digits than its factorization.

55578220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2778920 (or 2778918 counting only the distinct ones).

The product of its (nonzero) digits is 28000, while the sum is 34.

The square root of 55578220 is about 7455.0801471212. The cubic root of 55578220 is about 381.6232957546.

The spelling of 55578220 in words is "fifty-five million, five hundred seventy-eight thousand, two hundred twenty".