128759990 has 16 divisors (see below), whose sum is σ = 232260480. Its totient is φ = 51394560.

The previous prime is 128759987. The next prime is 128759999. The reversal of 128759990 is 99957821.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128759999) 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, 8651 + ... + 18230.

It is an arithmetic number, because the mean of its divisors is an integer number (14516280).

Almost surely, 2^128759990 is an apocalyptic number.

128759990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128759990 is a deficient number, since it is larger than the sum of its proper divisors (103500490).

128759990 is a wasteful number, since it uses less digits than its factorization.

128759990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27367.

The product of its (nonzero) digits is 408240, while the sum is 50.

The square root of 128759990 is about 11347.2459213679. The cubic root of 128759990 is about 504.9638767744.

The spelling of 128759990 in words is "one hundred twenty-eight million, seven hundred fifty-nine thousand, nine hundred ninety".