121761536556 has 96 divisors (see below), whose sum is σ = 326350725120. Its totient is φ = 34944782400.

The previous prime is 121761536539. The next prime is 121761536569. The reversal of 121761536556 is 655635167121.

It is a super-2 number, since 2×121761536556² (a number of 23 digits) contains 22 as substring.

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, 12211485 + ... + 12221451.

It is an arithmetic number, because the mean of its divisors is an integer number (3399486720).

Almost surely, 2^121761536556 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 121761536556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163175362560).

121761536556 is an abundant number, since it is smaller than the sum of its proper divisors (204589188564).

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

121761536556 is a wasteful number, since it uses less digits than its factorization.

121761536556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14875 (or 14873 counting only the distinct ones).

The product of its digits is 1134000, while the sum is 48.

The spelling of 121761536556 in words is "one hundred twenty-one billion, seven hundred sixty-one million, five hundred thirty-six thousand, five hundred fifty-six".