128694825 has 90 divisors (see below), whose sum is σ = 277521486. Its totient is φ = 58786560.

The previous prime is 128694823. The next prime is 128694827. The reversal of 128694825 is 528496821.

It is an interprime number because it is at equal distance from previous prime (128694823) and next prime (128694827).

It can be written as a sum of positive squares in 3 ways, for example, as 42928704 + 85766121 = 6552^2 + 9261^2 .

It is not a de Polignac number, because 128694825 - 2¹ = 128694823 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (128694823) by changing a digit.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 98577 + ... + 99873.

Almost surely, 2^128694825 is an apocalyptic number.

128694825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128694825 is an abundant number, since it is smaller than the sum of its proper divisors (148826661).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128694825 is a wasteful number, since it uses less digits than its factorization.

128694825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333 (or 1312 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 128694825 is about 11344.3741563825. The cubic root of 128694825 is about 504.8786755567.

The spelling of 128694825 in words is "one hundred twenty-eight million, six hundred ninety-four thousand, eight hundred twenty-five".