128890 has 8 divisors (see below), whose sum is σ = 232020. Its totient is φ = 51552.

The previous prime is 128879. The next prime is 128903. The reversal of 128890 is 98821.

It can be written as a sum of positive squares in 2 ways, for example, as 128881 + 9 = 359^2 + 3^2 .

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

It is a super-2 number, since 2×128890² = 33225264200, which contains 22 as substring.

It is a plaindrome in base 13.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 6435 + ... + 6454.

2¹²⁸⁸⁹⁰ is an apocalyptic number.

128890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128890 is a deficient number, since it is larger than the sum of its proper divisors (103130).

128890 is a wasteful number, since it uses less digits than its factorization.

128890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12896.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 128890 is about 359.0125346001. The cubic root of 128890 is about 50.5133774971.

It can be divided in two parts, 1288 and 90, that added together give a triangular number (1378 = T₅₂).

The spelling of 128890 in words is "one hundred twenty-eight thousand, eight hundred ninety".