128642143 has 4 divisors (see below), whose sum is σ = 147019600. Its totient is φ = 110264688.

The previous prime is 128642123. The next prime is 128642153. The reversal of 128642143 is 341246821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 341246821 = 19 ⋅17960359.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128642143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128642123) 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, 9188718 + ... + 9188731.

It is an arithmetic number, because the mean of its divisors is an integer number (36754900).

Almost surely, 2^128642143 is an apocalyptic number.

128642143 is a deficient number, since it is larger than the sum of its proper divisors (18377457).

128642143 is an equidigital number, since it uses as much as digits as its factorization.

128642143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18377456.

The product of its digits is 9216, while the sum is 31.

The square root of 128642143 is about 11342.0519748412. The cubic root of 128642143 is about 504.8097744475.

Adding to 128642143 its reverse (341246821), we get a palindrome (469888964).

The spelling of 128642143 in words is "one hundred twenty-eight million, six hundred forty-two thousand, one hundred forty-three".