121755717136 has 80 divisors (see below), whose sum is σ = 262389456000. Its totient is φ = 54437402624.

The previous prime is 121755717091. The next prime is 121755717137. The reversal of 121755717136 is 631717557121.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is not an unprimeable number, because it can be changed into a prime (121755717137) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 866835 + ... + 997453.

It is an arithmetic number, because the mean of its divisors is an integer number (3279868200).

Almost surely, 2^121755717136 is an apocalyptic number.

121755717136 is a gapful number since it is divisible by the number (16) 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 121755717136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131194728000).

121755717136 is an abundant number, since it is smaller than the sum of its proper divisors (140633738864).

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

121755717136 is a wasteful number, since it uses less digits than its factorization.

121755717136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130816 (or 130810 counting only the distinct ones).

The product of its digits is 308700, while the sum is 46.

The spelling of 121755717136 in words is "one hundred twenty-one billion, seven hundred fifty-five million, seven hundred seventeen thousand, one hundred thirty-six".