128851997 has 2 divisors, whose sum is σ = 128851998. Its totient is φ = 128851996.

The previous prime is 128851969. The next prime is 128852021. The reversal of 128851997 is 799158821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116942596 + 11909401 = 10814^2 + 3451^2 .

It is an emirp because it is prime and its reverse (799158821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128851997 - 2⁸ = 128851741 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128851927) 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, 64425998 + 64425999.

It is an arithmetic number, because the mean of its divisors is an integer number (64425999).

Almost surely, 2^128851997 is an apocalyptic number.

It is an amenable number.

128851997 is a deficient number, since it is larger than the sum of its proper divisors (1).

128851997 is an equidigital number, since it uses as much as digits as its factorization.

128851997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 362880, while the sum is 50.

The square root of 128851997 is about 11351.2993529375. The cubic root of 128851997 is about 505.0841241420.

The spelling of 128851997 in words is "one hundred twenty-eight million, eight hundred fifty-one thousand, nine hundred ninety-seven".