128376528125781 has 32 divisors (see below), whose sum is σ = 185181477586560. Its totient is φ = 78638543149824.

The previous prime is 128376528125759. The next prime is 128376528125801. The reversal of 128376528125781 is 187521825673821.

It is not a de Polignac number, because 128376528125781 - 2²³ = 128376519737173 is a prime.

It is a super-2 number, since 2×128376528125781² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128376528125701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38805895 + ... + 41983931.

It is an arithmetic number, because the mean of its divisors is an integer number (5786921174580).

Almost surely, 2^{128376528125781} is an apocalyptic number.

It is an amenable number.

128376528125781 is a deficient number, since it is larger than the sum of its proper divisors (56804949460779).

128376528125781 is a wasteful number, since it uses less digits than its factorization.

128376528125781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3182805.

The product of its digits is 90316800, while the sum is 66.

The spelling of 128376528125781 in words is "one hundred twenty-eight trillion, three hundred seventy-six billion, five hundred twenty-eight million, one hundred twenty-five thousand, seven hundred eighty-one".