55531224 has 128 divisors (see below), whose sum is σ = 185664000. Its totient is φ = 15023232.

The previous prime is 55531211. The next prime is 55531241. The reversal of 55531224 is 42213555.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27762 + ... + 29694.

It is an arithmetic number, because the mean of its divisors is an integer number (1450500).

Almost surely, 2^55531224 is an apocalyptic number.

55531224 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55531224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92832000).

55531224 is an abundant number, since it is smaller than the sum of its proper divisors (130132776).

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

55531224 is a wasteful number, since it uses less digits than its factorization.

55531224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1974 (or 1964 counting only the distinct ones).

The product of its digits is 6000, while the sum is 27.

The square root of 55531224 is about 7451.9275358796. The cubic root of 55531224 is about 381.5157006937.

Adding to 55531224 its reverse (42213555), we get a palindrome (97744779).

It can be divided in two parts, 55531 and 224, that added together give a palindrome (55755).

The spelling of 55531224 in words is "fifty-five million, five hundred thirty-one thousand, two hundred twenty-four".