128409581757406 has 4 divisors (see below), whose sum is σ = 192614372636112. Its totient is φ = 64204790878702.

The previous prime is 128409581757343. The next prime is 128409581757433. The reversal of 128409581757406 is 604757185904821.

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

It is a super-2 number, since 2×128409581757406² (a number of 29 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32102395439350 + ... + 32102395439353.

It is an arithmetic number, because the mean of its divisors is an integer number (48153593159028).

Almost surely, 2^{128409581757406} is an apocalyptic number.

128409581757406 is a deficient number, since it is larger than the sum of its proper divisors (64204790878706).

128409581757406 is an equidigital number, since it uses as much as digits as its factorization.

128409581757406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64204790878705.

The product of its (nonzero) digits is 135475200, while the sum is 67.

The spelling of 128409581757406 in words is "one hundred twenty-eight trillion, four hundred nine billion, five hundred eighty-one million, seven hundred fifty-seven thousand, four hundred six".