55021213331 has 4 divisors (see below), whose sum is σ = 62881386672. Its totient is φ = 47161039992.

The previous prime is 55021213309. The next prime is 55021213339. The reversal of 55021213331 is 13331212055.

55021213331 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 55021213331 - 2²⁶ = 54954104467 is a prime.

It is a super-2 number, since 2×55021213331² (a number of 22 digits) contains 22 as substring.

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 55021213331.

It is not an unprimeable number, because it can be changed into a prime (55021213339) 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, 3930086660 + ... + 3930086673.

It is an arithmetic number, because the mean of its divisors is an integer number (15720346668).

Almost surely, 2^55021213331 is an apocalyptic number.

55021213331 is a deficient number, since it is larger than the sum of its proper divisors (7860173341).

55021213331 is an equidigital number, since it uses as much as digits as its factorization.

55021213331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7860173340.

The product of its (nonzero) digits is 2700, while the sum is 26.

Adding to 55021213331 its reverse (13331212055), we get a palindrome (68352425386).

The spelling of 55021213331 in words is "fifty-five billion, twenty-one million, two hundred thirteen thousand, three hundred thirty-one".