128442931 has 8 divisors (see below), whose sum is σ = 130137840. Its totient is φ = 126753792.

The previous prime is 128442929. The next prime is 128442949. The reversal of 128442931 is 139244821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128442931 - 2¹ = 128442929 is a prime.

It is a super-4 number, since 4×128442931⁴ (a number of 34 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128442911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59731 + ... + 61843.

It is an arithmetic number, because the mean of its divisors is an integer number (16267230).

Almost surely, 2^128442931 is an apocalyptic number.

128442931 is a deficient number, since it is larger than the sum of its proper divisors (1694909).

128442931 is an equidigital number, since it uses as much as digits as its factorization.

128442931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2885.

The product of its digits is 13824, while the sum is 34.

The square root of 128442931 is about 11333.2665635288. The cubic root of 128442931 is about 504.5490612330.

The spelling of 128442931 in words is "one hundred twenty-eight million, four hundred forty-two thousand, nine hundred thirty-one".