128513139 has 4 divisors (see below), whose sum is σ = 171350856. Its totient is φ = 85675424.

The previous prime is 128513113. The next prime is 128513159. The reversal of 128513139 is 931315821.

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

It is a cyclic number.

It is not a de Polignac number, because 128513139 - 2⁸ = 128512883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128513159) 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, 21418854 + ... + 21418859.

It is an arithmetic number, because the mean of its divisors is an integer number (42837714).

Almost surely, 2^128513139 is an apocalyptic number.

128513139 is a deficient number, since it is larger than the sum of its proper divisors (42837717).

128513139 is an equidigital number, since it uses as much as digits as its factorization.

128513139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42837716.

The product of its digits is 6480, while the sum is 33.

The square root of 128513139 is about 11336.3635703871. The cubic root of 128513139 is about 504.6409747595.

The spelling of 128513139 in words is "one hundred twenty-eight million, five hundred thirteen thousand, one hundred thirty-nine".