128723 has 12 divisors (see below), whose sum is σ = 155952. Its totient is φ = 105840.

The previous prime is 128717. The next prime is 128747. The reversal of 128723 is 327821.

It is not a de Polignac number, because 128723 - 2⁶ = 128659 is a prime.

It is a super-2 number, since 2×128723² = 33139221458, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (128923) 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, 1778 + ... + 1848.

It is an arithmetic number, because the mean of its divisors is an integer number (12996).

2¹²⁸⁷²³ is an apocalyptic number.

128723 is a deficient number, since it is larger than the sum of its proper divisors (27229).

128723 is an equidigital number, since it uses as much as digits as its factorization.

128723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 115 counting only the distinct ones).

The product of its digits is 672, while the sum is 23.

The square root of 128723 is about 358.7798768047. The cubic root of 128723 is about 50.4915517024.

The spelling of 128723 in words is "one hundred twenty-eight thousand, seven hundred twenty-three".