121688 has 32 divisors (see below), whose sum is σ = 272160. Its totient is φ = 49920.

The previous prime is 121687. The next prime is 121697. The reversal of 121688 is 886121.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2270 + ... + 2322.

It is an arithmetic number, because the mean of its divisors is an integer number (8505).

2¹²¹⁶⁸⁸ 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 121688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136080).

121688 is an abundant number, since it is smaller than the sum of its proper divisors (150472).

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

121688 is a wasteful number, since it uses less digits than its factorization.

121688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 103 counting only the distinct ones).

The product of its digits is 768, while the sum is 26.

The square root of 121688 is about 348.8380713168. The cubic root of 121688 is about 49.5544413435.

It can be divided in two parts, 12168 and 8, that multiplied together give a square (97344 = 312²).

The spelling of 121688 in words is "one hundred twenty-one thousand, six hundred eighty-eight".