55281920 has 36 divisors (see below), whose sum is σ = 132420540. Its totient is φ = 22112256.

The previous prime is 55281913. The next prime is 55281929. The reversal of 55281920 is 2918255.

It can be written as a sum of positive squares in 2 ways, for example, as 8386816 + 46895104 = 2896^2 + 6848^2 .

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (55281929) 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, 20315 + ... + 22874.

Almost surely, 2^55281920 is an apocalyptic number.

It is an amenable number.

55281920 is an abundant number, since it is smaller than the sum of its proper divisors (77138620).

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

55281920 is an equidigital number, since it uses as much as digits as its factorization.

55281920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43210 (or 43196 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 55281920 is about 7435.1812351818. The cubic root of 55281920 is about 380.9439137801.

The spelling of 55281920 in words is "fifty-five million, two hundred eighty-one thousand, nine hundred twenty".