128745 has 12 divisors (see below), whose sum is σ = 223236. Its totient is φ = 68640.

The previous prime is 128717. The next prime is 128747. The reversal of 128745 is 547821.

It can be written as a sum of positive squares in 2 ways, for example, as 59049 + 69696 = 243^2 + 264^2 .

It is not a de Polignac number, because 128745 - 2⁸ = 128489 is a prime.

128745 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (128747) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1386 + ... + 1475.

It is an arithmetic number, because the mean of its divisors is an integer number (18603).

2¹²⁸⁷⁴⁵ is an apocalyptic number.

128745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128745 is a deficient number, since it is larger than the sum of its proper divisors (94491).

128745 is a wasteful number, since it uses less digits than its factorization.

128745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2872 (or 2869 counting only the distinct ones).

The product of its digits is 2240, while the sum is 27.

The square root of 128745 is about 358.8105349624. The cubic root of 128745 is about 50.4944280360.

The spelling of 128745 in words is "one hundred twenty-eight thousand, seven hundred forty-five".