15500522221320 has 128 divisors (see below), whose sum is σ = 47142552124800. Its totient is φ = 4076505667584.

The previous prime is 15500522221297. The next prime is 15500522221357. The reversal of 15500522221320 is 2312222500551.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 113627874 + ... + 113764206.

It is an arithmetic number, because the mean of its divisors is an integer number (368301188475).

Almost surely, 2^{15500522221320} is an apocalyptic number.

15500522221320 is a gapful number since it is divisible by the number (10) 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 15500522221320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23571276062400).

15500522221320 is an abundant number, since it is smaller than the sum of its proper divisors (31642029903480).

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

15500522221320 is a wasteful number, since it uses less digits than its factorization.

15500522221320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149399 (or 149395 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 15500522221320 its reverse (2312222500551), we get a palindrome (17812744721871).

The spelling of 15500522221320 in words is "fifteen trillion, five hundred billion, five hundred twenty-two million, two hundred twenty-one thousand, three hundred twenty".