1221152134500 has 288 divisors, whose sum is σ = 4124789192160. Its totient is φ = 303039897600.

The previous prime is 1221152134457. The next prime is 1221152134549. The reversal of 1221152134500 is 54312511221.

It is a happy number.

1221152134500 is a `hidden beast` number, since 1 + 2 + 2 + 1 + 152 + 1 + 3 + 4 + 500 = 666.

It can be written as a sum of positive squares in 16 ways, for example, as 546168297024 + 674983837476 = 739032^2 + 821574^2 .

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 95 ways as a sum of consecutive naturals, for example, 6718822 + ... + 6898178.

It is an arithmetic number, because the mean of its divisors is an integer number (14322184695).

Almost surely, 2^{1221152134500} is an apocalyptic number.

1221152134500 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 1221152134500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2062394596080).

1221152134500 is an abundant number, since it is smaller than the sum of its proper divisors (2903637057660).

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

1221152134500 is a wasteful number, since it uses less digits than its factorization.

1221152134500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179488 (or 179473 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 1221152134500 its reverse (54312511221), we get a palindrome (1275464645721).

The spelling of 1221152134500 in words is "one trillion, two hundred twenty-one billion, one hundred fifty-two million, one hundred thirty-four thousand, five hundred".