128537 has 4 divisors (see below), whose sum is σ = 136116. Its totient is φ = 120960.

The previous prime is 128521. The next prime is 128549. The reversal of 128537 is 735821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 65536 + 63001 = 256^2 + 251^2 .

It is a cyclic number.

It is not a de Polignac number, because 128537 - 2⁴ = 128521 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 128537.

It is not an unprimeable number, because it can be changed into a prime (128237) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3764 + ... + 3797.

It is an arithmetic number, because the mean of its divisors is an integer number (34029).

2¹²⁸⁵³⁷ is an apocalyptic number.

128537 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

128537 is a deficient number, since it is larger than the sum of its proper divisors (7579).

128537 is an equidigital number, since it uses as much as digits as its factorization.

128537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7578.

The product of its digits is 1680, while the sum is 26.

The square root of 128537 is about 358.5205712369. The cubic root of 128537 is about 50.4672205011.

The spelling of 128537 in words is "one hundred twenty-eight thousand, five hundred thirty-seven".