128889870 has 64 divisors (see below), whose sum is σ = 321753600. Its totient is φ = 33015168.

The previous prime is 128889857. The next prime is 128889883. The reversal of 128889870 is 78988821.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (128889857) and next prime (128889883).

It is a super-2 number, since 2×128889870² = 33225197177233800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91431 + ... + 92829.

It is an arithmetic number, because the mean of its divisors is an integer number (5027400).

Almost surely, 2^128889870 is an apocalyptic number.

128889870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128889870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160876800).

128889870 is an abundant number, since it is smaller than the sum of its proper divisors (192863730).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128889870 is a wasteful number, since it uses less digits than its factorization.

128889870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1529.

The product of its (nonzero) digits is 516096, while the sum is 51.

The square root of 128889870 is about 11352.9674534899. The cubic root of 128889870 is about 505.1336051424.

The spelling of 128889870 in words is "one hundred twenty-eight million, eight hundred eighty-nine thousand, eight hundred seventy".