128968990 has 32 divisors (see below), whose sum is σ = 240387840. Its totient is φ = 49766400.

The previous prime is 128968967. The next prime is 128968993. The reversal of 128968990 is 99869821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128968993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167326 + ... + 168094.

It is an arithmetic number, because the mean of its divisors is an integer number (7512120).

Almost surely, 2^128968990 is an apocalyptic number.

128968990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128968990 is a deficient number, since it is larger than the sum of its proper divisors (111418850).

128968990 is a wasteful number, since it uses less digits than its factorization.

128968990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1348.

The product of its (nonzero) digits is 559872, while the sum is 52.

The square root of 128968990 is about 11356.4514704198. The cubic root of 128968990 is about 505.2369440001.

The spelling of 128968990 in words is "one hundred twenty-eight million, nine hundred sixty-eight thousand, nine hundred ninety".