121161217824 has 120 divisors (see below), whose sum is σ = 356461389900. Its totient is φ = 40372383744.

The previous prime is 121161217823. The next prime is 121161217831. The reversal of 121161217824 is 428712161121.

121161217824 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 612 + 17 + 8 + 24 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 116054686224 + 5106531600 = 340668^2 + 71460^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (121161217823) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8933032 + ... + 8946584.

Almost surely, 2^121161217824 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 121161217824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178230694950).

121161217824 is an abundant number, since it is smaller than the sum of its proper divisors (235300172076).

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

121161217824 is a wasteful number, since it uses less digits than its factorization.

121161217824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17024 (or 17007 counting only the distinct ones).

The product of its digits is 10752, while the sum is 36.

Adding to 121161217824 its reverse (428712161121), we get a palindrome (549873378945).

The spelling of 121161217824 in words is "one hundred twenty-one billion, one hundred sixty-one million, two hundred seventeen thousand, eight hundred twenty-four".