128840461 has 2 divisors, whose sum is σ = 128840462. Its totient is φ = 128840460.

The previous prime is 128840447. The next prime is 128840471. The reversal of 128840461 is 164048821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128391561 + 448900 = 11331^2 + 670^2 .

It is a cyclic number.

It is not a de Polignac number, because 128840461 - 2⁵ = 128840429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128840471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64420230 + 64420231.

It is an arithmetic number, because the mean of its divisors is an integer number (64420231).

Almost surely, 2^128840461 is an apocalyptic number.

It is an amenable number.

128840461 is a deficient number, since it is larger than the sum of its proper divisors (1).

128840461 is an equidigital number, since it uses as much as digits as its factorization.

128840461 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12288, while the sum is 34.

The square root of 128840461 is about 11350.7912059028. The cubic root of 128840461 is about 505.0690504541.

The spelling of 128840461 in words is "one hundred twenty-eight million, eight hundred forty thousand, four hundred sixty-one".