121542221152 has 96 divisors (see below), whose sum is σ = 282205486080. Its totient is φ = 50924090880.

The previous prime is 121542221111. The next prime is 121542221161. The reversal of 121542221152 is 251122245121.

It is a self number, because there is not a number n which added to its sum of digits gives 121542221152.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1873 + ... + 493039.

It is an arithmetic number, because the mean of its divisors is an integer number (2939640480).

Almost surely, 2^121542221152 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 121542221152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141102743040).

121542221152 is an abundant number, since it is smaller than the sum of its proper divisors (160663264928).

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

121542221152 is a wasteful number, since it uses less digits than its factorization.

121542221152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491244 (or 491236 counting only the distinct ones).

The product of its digits is 3200, while the sum is 28.

Adding to 121542221152 its reverse (251122245121), we get a palindrome (372664466273).

The spelling of 121542221152 in words is "one hundred twenty-one billion, five hundred forty-two million, two hundred twenty-one thousand, one hundred fifty-two".