128888890 has 16 divisors (see below), whose sum is σ = 249846408. Its totient is φ = 47589696.

The previous prime is 128888869. The next prime is 128888891. The reversal of 128888890 is 98888821.

It can be written as a sum of positive squares in 4 ways, for example, as 103978809 + 24910081 = 10197^2 + 4991^2 .

It is a super-2 number, since 2×128888890² = 33224691930864200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (128888891) 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, 495597 + ... + 495856.

Almost surely, 2^128888890 is an apocalyptic number.

128888890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128888890 is a deficient number, since it is larger than the sum of its proper divisors (120957518).

128888890 is a wasteful number, since it uses less digits than its factorization.

128888890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991473.

The product of its (nonzero) digits is 589824, while the sum is 52.

The square root of 128888890 is about 11352.9242928860. The cubic root of 128888890 is about 505.1323248965.

The spelling of 128888890 in words is "one hundred twenty-eight million, eight hundred eighty-eight thousand, eight hundred ninety".