128831025 has 12 divisors (see below), whose sum is σ = 213000752. Its totient is φ = 68709840.

The previous prime is 128831011. The next prime is 128831063. The reversal of 128831025 is 520138821.

It is not a de Polignac number, because 128831025 - 2⁵ = 128830993 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 128830983 and 128831001.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 858799 + ... + 858948.

Almost surely, 2^128831025 is an apocalyptic number.

128831025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128831025 is a deficient number, since it is larger than the sum of its proper divisors (84169727).

128831025 is a wasteful number, since it uses less digits than its factorization.

128831025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1717760 (or 1717755 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 128831025 is about 11350.3755444479. The cubic root of 128831025 is about 505.0567200939.

Adding to 128831025 its reverse (520138821), we get a palindrome (648969846).

The spelling of 128831025 in words is "one hundred twenty-eight million, eight hundred thirty-one thousand, twenty-five".