55155220 has 12 divisors (see below), whose sum is σ = 115826004. Its totient is φ = 22062080.

The previous prime is 55155179. The next prime is 55155227. The reversal of 55155220 is 2255155.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12931216 + 42224004 = 3596^2 + 6498^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55155227) 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, 1378861 + ... + 1378900.

It is an arithmetic number, because the mean of its divisors is an integer number (9652167).

Almost surely, 2^55155220 is an apocalyptic number.

It is an amenable number.

55155220 is an abundant number, since it is smaller than the sum of its proper divisors (60670784).

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

55155220 is a wasteful number, since it uses less digits than its factorization.

55155220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2757770 (or 2757768 counting only the distinct ones).

The product of its (nonzero) digits is 2500, while the sum is 25.

The square root of 55155220 is about 7426.6560442773. The cubic root of 55155220 is about 380.6526641634.

The spelling of 55155220 in words is "fifty-five million, one hundred fifty-five thousand, two hundred twenty".