128001433860281 has 4 divisors (see below), whose sum is σ = 128001645663012. Its totient is φ = 128001222057552.

The previous prime is 128001433860277. The next prime is 128001433860299. The reversal of 128001433860281 is 182068334100821.

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 50995894781881 + 77005539078400 = 7141141^2 + 8775280^2 .

It is a cyclic number.

It is not a de Polignac number, because 128001433860281 - 2² = 128001433860277 is a prime.

It is a super-2 number, since 2×128001433860281² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128001433860221) 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, 104992250 + ... + 106204403.

It is an arithmetic number, because the mean of its divisors is an integer number (32000411415753).

Almost surely, 2^{128001433860281} is an apocalyptic number.

It is an amenable number.

128001433860281 is a deficient number, since it is larger than the sum of its proper divisors (211802731).

128001433860281 is an equidigital number, since it uses as much as digits as its factorization.

128001433860281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211802730.

The product of its (nonzero) digits is 442368, while the sum is 47.

The spelling of 128001433860281 in words is "one hundred twenty-eight trillion, one billion, four hundred thirty-three million, eight hundred sixty thousand, two hundred eighty-one".