55121331320 has 64 divisors (see below), whose sum is σ = 135612195840. Its totient is φ = 19997545600.

The previous prime is 55121331263. The next prime is 55121331383. The reversal of 55121331320 is 2313312155.

It is a super-2 number, since 2×55121331320² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55121331320.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44309 + ... + 334971.

It is an arithmetic number, because the mean of its divisors is an integer number (2118940560).

Almost surely, 2^55121331320 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 55121331320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67806097920).

55121331320 is an abundant number, since it is smaller than the sum of its proper divisors (80490864520).

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

55121331320 is a wasteful number, since it uses less digits than its factorization.

55121331320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291116 (or 291112 counting only the distinct ones).

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

Adding to 55121331320 its reverse (2313312155), we get a palindrome (57434643475).

The spelling of 55121331320 in words is "fifty-five billion, one hundred twenty-one million, three hundred thirty-one thousand, three hundred twenty".