128978141 has 4 divisors (see below), whose sum is σ = 129002172. Its totient is φ = 128954112.

The previous prime is 128978123. The next prime is 128978147. The reversal of 128978141 is 141879821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 73788100 + 55190041 = 8590^2 + 7429^2 .

It is a cyclic number.

It is not a de Polignac number, because 128978141 - 2¹⁴ = 128961757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128978147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125 + ... + 16061.

It is an arithmetic number, because the mean of its divisors is an integer number (32250543).

Almost surely, 2^128978141 is an apocalyptic number.

It is an amenable number.

128978141 is a deficient number, since it is larger than the sum of its proper divisors (24031).

128978141 is an equidigital number, since it uses as much as digits as its factorization.

128978141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24030.

The product of its digits is 32256, while the sum is 41.

The square root of 128978141 is about 11356.8543620142. The cubic root of 128978141 is about 505.2488934202.

The spelling of 128978141 in words is "one hundred twenty-eight million, nine hundred seventy-eight thousand, one hundred forty-one".