128637825 has 24 divisors (see below), whose sum is σ = 217212288. Its totient is φ = 67145280.

The previous prime is 128637797. The next prime is 128637829. The reversal of 128637825 is 528736821.

It is not a de Polignac number, because 128637825 - 2²⁵ = 95083393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128637829) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14722 + ... + 21771.

It is an arithmetic number, because the mean of its divisors is an integer number (9050512).

Almost surely, 2^128637825 is an apocalyptic number.

128637825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128637825 is a deficient number, since it is larger than the sum of its proper divisors (88574463).

128637825 is a wasteful number, since it uses less digits than its factorization.

128637825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36553 (or 36548 counting only the distinct ones).

The product of its digits is 161280, while the sum is 42.

The square root of 128637825 is about 11341.8616196813. The cubic root of 128637825 is about 504.8041262389.

The spelling of 128637825 in words is "one hundred twenty-eight million, six hundred thirty-seven thousand, eight hundred twenty-five".