121688140 has 48 divisors (see below), whose sum is σ = 293090112. Its totient is φ = 41573376.

The previous prime is 121688137. The next prime is 121688143. The reversal of 121688140 is 41886121.

It is an interprime number because it is at equal distance from previous prime (121688137) and next prime (121688143).

It is not an unprimeable number, because it can be changed into a prime (121688143) 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, 42432 + ... + 45208.

It is an arithmetic number, because the mean of its divisors is an integer number (6106044).

Almost surely, 2^121688140 is an apocalyptic number.

121688140 is a gapful number since it is divisible by the number (10) 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 121688140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146545056).

121688140 is an abundant number, since it is smaller than the sum of its proper divisors (171401972).

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

121688140 is a wasteful number, since it uses less digits than its factorization.

121688140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3106 (or 3104 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 31.

The square root of 121688140 is about 11031.2347450319. The cubic root of 121688140 is about 495.5446034731.

The spelling of 121688140 in words is "one hundred twenty-one million, six hundred eighty-eight thousand, one hundred forty".