128977 has 4 divisors (see below), whose sum is σ = 130356. Its totient is φ = 127600.

The previous prime is 128971. The next prime is 128981. The reversal of 128977 is 779821.

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 108241 + 20736 = 329^2 + 144^2 .

It is a cyclic number.

It is not a de Polignac number, because 128977 - 2³ = 128969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128971) 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, 538 + ... + 739.

It is an arithmetic number, because the mean of its divisors is an integer number (32589).

2¹²⁸⁹⁷⁷ is an apocalyptic number.

It is an amenable number.

128977 is a deficient number, since it is larger than the sum of its proper divisors (1379).

128977 is a wasteful number, since it uses less digits than its factorization.

128977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378.

The product of its digits is 7056, while the sum is 34.

The square root of 128977 is about 359.1336798464. The cubic root of 128977 is about 50.5247403528.

The spelling of 128977 in words is "one hundred twenty-eight thousand, nine hundred seventy-seven".