55440121321 has 32 divisors (see below), whose sum is σ = 62664053760. Its totient is φ = 48732324480.

The previous prime is 55440121313. The next prime is 55440121351. The reversal of 55440121321 is 12312104455.

It is not a de Polignac number, because 55440121321 - 2³ = 55440121313 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 55440121321.

It is not an unprimeable number, because it can be changed into a prime (55440121351) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38526120 + ... + 38527558.

It is an arithmetic number, because the mean of its divisors is an integer number (1958251680).

Almost surely, 2^55440121321 is an apocalyptic number.

It is an amenable number.

55440121321 is a deficient number, since it is larger than the sum of its proper divisors (7223932439).

55440121321 is an equidigital number, since it uses as much as digits as its factorization.

55440121321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1618 (or 1536 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

Adding to 55440121321 its reverse (12312104455), we get a palindrome (67752225776).

The spelling of 55440121321 in words is "fifty-five billion, four hundred forty million, one hundred twenty-one thousand, three hundred twenty-one".