121345128 has 80 divisors (see below), whose sum is σ = 341626560. Its totient is φ = 40240800.

The previous prime is 121345121. The next prime is 121345151. The reversal of 121345128 is 821543121.

121345128 is a `hidden beast` number, since 12 + 134 + 512 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (121345121) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 175263 + ... + 175953.

It is an arithmetic number, because the mean of its divisors is an integer number (4270332).

Almost surely, 2^121345128 is an apocalyptic number.

121345128 is a gapful number since it is divisible by the number (18) 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 121345128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170813280).

121345128 is an abundant number, since it is smaller than the sum of its proper divisors (220281432).

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

121345128 is a wasteful number, since it uses less digits than its factorization.

121345128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980 (or 967 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 121345128 is about 11015.6764658372. The cubic root of 121345128 is about 495.0785550260.

Adding to 121345128 its reverse (821543121), we get a palindrome (942888249).

The spelling of 121345128 in words is "one hundred twenty-one million, three hundred forty-five thousand, one hundred twenty-eight".