55578216 has 16 divisors (see below), whose sum is σ = 138945600. Its totient is φ = 18526064.

The previous prime is 55578209. The next prime is 55578217. The reversal of 55578216 is 61287555.

It is not an unprimeable number, because it can be changed into a prime (55578217) 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, 1157856 + ... + 1157903.

It is an arithmetic number, because the mean of its divisors is an integer number (8684100).

Almost surely, 2^55578216 is an apocalyptic number.

It is an amenable number.

55578216 is an abundant number, since it is smaller than the sum of its proper divisors (83367384).

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

55578216 is a wasteful number, since it uses less digits than its factorization.

55578216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2315768 (or 2315764 counting only the distinct ones).

The product of its digits is 84000, while the sum is 39.

The square root of 55578216 is about 7455.0798788477. The cubic root of 55578216 is about 381.6232865994.

The spelling of 55578216 in words is "fifty-five million, five hundred seventy-eight thousand, two hundred sixteen".