128199761 has 2 divisors, whose sum is σ = 128199762. Its totient is φ = 128199760.

The previous prime is 128199733. The next prime is 128199781. The reversal of 128199761 is 167991821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120670225 + 7529536 = 10985^2 + 2744^2 .

It is a cyclic number.

It is not a de Polignac number, because 128199761 - 2⁶ = 128199697 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128199781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64099880 + 64099881.

It is an arithmetic number, because the mean of its divisors is an integer number (64099881).

Almost surely, 2^128199761 is an apocalyptic number.

It is an amenable number.

128199761 is a deficient number, since it is larger than the sum of its proper divisors (1).

128199761 is an equidigital number, since it uses as much as digits as its factorization.

128199761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 44.

The square root of 128199761 is about 11322.5333296043. The cubic root of 128199761 is about 504.2304535766.

The spelling of 128199761 in words is "one hundred twenty-eight million, one hundred ninety-nine thousand, seven hundred sixty-one".