128681890 has 16 divisors (see below), whose sum is σ = 231815808. Its totient is φ = 51430896.

The previous prime is 128681881. The next prime is 128681909. The reversal of 128681890 is 98186821.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9709 + ... + 18751.

It is an arithmetic number, because the mean of its divisors is an integer number (14488488).

Almost surely, 2^128681890 is an apocalyptic number.

128681890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128681890 is a deficient number, since it is larger than the sum of its proper divisors (103133918).

128681890 is a wasteful number, since it uses less digits than its factorization.

128681890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10473.

The product of its (nonzero) digits is 55296, while the sum is 43.

The square root of 128681890 is about 11343.8040356840. The cubic root of 128681890 is about 504.8617600242.

The spelling of 128681890 in words is "one hundred twenty-eight million, six hundred eighty-one thousand, eight hundred ninety".