128239615 has 12 divisors (see below), whose sum is σ = 179012376. Its totient is φ = 87935568.

The previous prime is 128239613. The next prime is 128239633. The reversal of 128239615 is 516932821.

It is not a de Polignac number, because 128239615 - 2¹ = 128239613 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 (128239613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 261469 + ... + 261958.

It is an arithmetic number, because the mean of its divisors is an integer number (14917698).

Almost surely, 2^128239615 is an apocalyptic number.

128239615 is a deficient number, since it is larger than the sum of its proper divisors (50772761).

128239615 is an equidigital number, since it uses as much as digits as its factorization.

128239615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523446 (or 523439 counting only the distinct ones).

The product of its digits is 25920, while the sum is 37.

The square root of 128239615 is about 11324.2931346729. The cubic root of 128239615 is about 504.2826989118.

The spelling of 128239615 in words is "one hundred twenty-eight million, two hundred thirty-nine thousand, six hundred fifteen".