128780417537 has 4 divisors (see below), whose sum is σ = 133221121620. Its totient is φ = 124339713456.

The previous prime is 128780417531. The next prime is 128780417567. The reversal of 128780417537 is 735714087821.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20186442241 + 108593975296 = 142079^2 + 329536^2 .

It is a cyclic number.

It is not a de Polignac number, because 128780417537 - 2⁶ = 128780417473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128780417531) 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, 2220351998 + ... + 2220352055.

It is an arithmetic number, because the mean of its divisors is an integer number (33305280405).

Almost surely, 2^128780417537 is an apocalyptic number.

It is an amenable number.

128780417537 is a deficient number, since it is larger than the sum of its proper divisors (4440704083).

128780417537 is an equidigital number, since it uses as much as digits as its factorization.

128780417537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4440704082.

The product of its (nonzero) digits is 2634240, while the sum is 53.

The spelling of 128780417537 in words is "one hundred twenty-eight billion, seven hundred eighty million, four hundred seventeen thousand, five hundred thirty-seven".