128977321 has 8 divisors (see below), whose sum is σ = 142069824. Its totient is φ = 116112720.

The previous prime is 128977313. The next prime is 128977327. The reversal of 128977321 is 123779821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128977321 - 2³ = 128977313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128977327) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55786 + ... + 58051.

It is an arithmetic number, because the mean of its divisors is an integer number (17758728).

Almost surely, 2^128977321 is an apocalyptic number.

128977321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

128977321 is a deficient number, since it is larger than the sum of its proper divisors (13092503).

128977321 is a wasteful number, since it uses less digits than its factorization.

128977321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113951.

The product of its digits is 42336, while the sum is 40.

The square root of 128977321 is about 11356.8182604108. The cubic root of 128977321 is about 505.2478226833.

The spelling of 128977321 in words is "one hundred twenty-eight million, nine hundred seventy-seven thousand, three hundred twenty-one".