55431321 has 16 divisors (see below), whose sum is σ = 80875200. Its totient is φ = 33491520.

The previous prime is 55431319. The next prime is 55431331. The reversal of 55431321 is 12313455.

55431321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 55431321 - 2¹ = 55431319 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 55431291 and 55431300.

It is not an unprimeable number, because it can be changed into a prime (55431331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9111 + ... + 13923.

It is an arithmetic number, because the mean of its divisors is an integer number (5054700).

Almost surely, 2^55431321 is an apocalyptic number.

It is an amenable number.

55431321 is a deficient number, since it is larger than the sum of its proper divisors (25443879).

55431321 is a wasteful number, since it uses less digits than its factorization.

55431321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5176.

The product of its digits is 1800, while the sum is 24.

The square root of 55431321 is about 7445.2213533246. The cubic root of 55431321 is about 381.2867757770.

Adding to 55431321 its reverse (12313455), we get a palindrome (67744776).

The spelling of 55431321 in words is "fifty-five million, four hundred thirty-one thousand, three hundred twenty-one".