161121121264044 has 288 divisors, whose sum is σ = 436075642941120. Its totient is φ = 49984384794624.

The previous prime is 161121121264001. The next prime is 161121121264063. The reversal of 161121121264044 is 440462121121161.

161121121264044 is a `hidden beast` number, since 1 + 6 + 1 + 1 + 2 + 1 + 1 + 2 + 1 + 2 + 640 + 4 + 4 = 666.

161121121264044 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 18044694972 + ... + 18044703900.

It is an arithmetic number, because the mean of its divisors is an integer number (1514151537990).

Almost surely, 2^{161121121264044} 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 161121121264044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (218037821470560).

161121121264044 is an abundant number, since it is smaller than the sum of its proper divisors (274954521677076).

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

161121121264044 is a wasteful number, since it uses less digits than its factorization.

161121121264044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10049 (or 10044 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The spelling of 161121121264044 in words is "one hundred sixty-one trillion, one hundred twenty-one billion, one hundred twenty-one million, two hundred sixty-four thousand, forty-four".