128726401 has 2 divisors, whose sum is σ = 128726402. Its totient is φ = 128726400.

The previous prime is 128726399. The next prime is 128726449. The reversal of 128726401 is 104627821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124099600 + 4626801 = 11140^2 + 2151^2 .

It is a cyclic number.

It is not a de Polignac number, because 128726401 - 2¹ = 128726399 is a prime.

Together with 128726399, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (128726491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64363200 + 64363201.

It is an arithmetic number, because the mean of its divisors is an integer number (64363201).

Almost surely, 2^128726401 is an apocalyptic number.

It is an amenable number.

128726401 is a deficient number, since it is larger than the sum of its proper divisors (1).

128726401 is an equidigital number, since it uses as much as digits as its factorization.

128726401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 128726401 is about 11345.7657740674. The cubic root of 128726401 is about 504.9199637888.

The spelling of 128726401 in words is "one hundred twenty-eight million, seven hundred twenty-six thousand, four hundred one".