128691743 has 8 divisors (see below), whose sum is σ = 133193760. Its totient is φ = 124254720.

The previous prime is 128691737. The next prime is 128691779. The reversal of 128691743 is 347196821.

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

It is a cyclic number.

It is not a de Polignac number, because 128691743 - 2⁶ = 128691679 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128691743.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128691443) 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, 12203 + ... + 20156.

It is an arithmetic number, because the mean of its divisors is an integer number (16649220).

Almost surely, 2^128691743 is an apocalyptic number.

128691743 is a deficient number, since it is larger than the sum of its proper divisors (4502017).

128691743 is an equidigital number, since it uses as much as digits as its factorization.

128691743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32497.

The product of its digits is 72576, while the sum is 41.

The square root of 128691743 is about 11344.2383173133. The cubic root of 128691743 is about 504.8746452250.

The spelling of 128691743 in words is "one hundred twenty-eight million, six hundred ninety-one thousand, seven hundred forty-three".