128981397 has 8 divisors (see below), whose sum is σ = 182091456. Its totient is φ = 80929472.

The previous prime is 128981393. The next prime is 128981407. The reversal of 128981397 is 793189821.

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 128981397 - 2² = 128981393 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128981393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1264473 + ... + 1264574.

It is an arithmetic number, because the mean of its divisors is an integer number (22761432).

Almost surely, 2^128981397 is an apocalyptic number.

128981397 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

128981397 is a deficient number, since it is larger than the sum of its proper divisors (53110059).

128981397 is a wasteful number, since it uses less digits than its factorization.

128981397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2529067.

The product of its digits is 217728, while the sum is 48.

The square root of 128981397 is about 11356.9977106628. The cubic root of 128981397 is about 505.2531449844.

The spelling of 128981397 in words is "one hundred twenty-eight million, nine hundred eighty-one thousand, three hundred ninety-seven".