128753781 has 8 divisors (see below), whose sum is σ = 184877280. Its totient is φ = 79233072.

The previous prime is 128753777. The next prime is 128753797. The reversal of 128753781 is 187357821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128753781 - 2² = 128753777 is a prime.

It is a super-2 number, since 2×128753781² = 33155072243591922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128753711) 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, 1650651 + ... + 1650728.

It is an arithmetic number, because the mean of its divisors is an integer number (23109660).

Almost surely, 2^128753781 is an apocalyptic number.

It is an amenable number.

128753781 is a deficient number, since it is larger than the sum of its proper divisors (56123499).

128753781 is a wasteful number, since it uses less digits than its factorization.

128753781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3301395.

The product of its digits is 94080, while the sum is 42.

The square root of 128753781 is about 11346.9723274537. The cubic root of 128753781 is about 504.9557599385.

The spelling of 128753781 in words is "one hundred twenty-eight million, seven hundred fifty-three thousand, seven hundred eighty-one".