55213312 has 72 divisors (see below), whose sum is σ = 137454912. Its totient is φ = 21504000.

The previous prime is 55213267. The next prime is 55213313. The reversal of 55213312 is 21331255.

It is a hoax number, since the sum of its digits (22) 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 (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55213313) 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 7 ways as a sum of consecutive naturals, for example, 18312 + ... + 21112.

It is an arithmetic number, because the mean of its divisors is an integer number (1909096).

Almost surely, 2^55213312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55213312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68727456).

55213312 is an abundant number, since it is smaller than the sum of its proper divisors (82241600).

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

55213312 is a wasteful number, since it uses less digits than its factorization.

55213312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2835 (or 2821 counting only the distinct ones).

The product of its digits is 900, while the sum is 22.

The square root of 55213312 is about 7430.5660618825. The cubic root of 55213312 is about 380.7862575367.

Adding to 55213312 its reverse (21331255), we get a palindrome (76544567).

The spelling of 55213312 in words is "fifty-five million, two hundred thirteen thousand, three hundred twelve".