128735567 has 4 divisors (see below), whose sum is σ = 130548816. Its totient is φ = 126922320.

The previous prime is 128735549. The next prime is 128735597. The reversal of 128735567 is 765537821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 765537821 = 3389 ⋅225889.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128735567 is a prime.

It is a super-2 number, since 2×128735567² = 33145692421622978, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128735527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 906518 + ... + 906659.

It is an arithmetic number, because the mean of its divisors is an integer number (32637204).

Almost surely, 2^128735567 is an apocalyptic number.

128735567 is a deficient number, since it is larger than the sum of its proper divisors (1813249).

128735567 is an equidigital number, since it uses as much as digits as its factorization.

128735567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1813248.

The product of its digits is 352800, while the sum is 44.

The square root of 128735567 is about 11346.1697061167. The cubic root of 128735567 is about 504.9319478276.

The spelling of 128735567 in words is "one hundred twenty-eight million, seven hundred thirty-five thousand, five hundred sixty-seven".