128759987 has 2 divisors, whose sum is σ = 128759988. Its totient is φ = 128759986.

The previous prime is 128759947. The next prime is 128759999. The reversal of 128759987 is 789957821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128759987 - 2⁶ = 128759923 is a prime.

It is not a weakly prime, because it can be changed into another prime (128759947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64379993 + 64379994.

It is an arithmetic number, because the mean of its divisors is an integer number (64379994).

Almost surely, 2^128759987 is an apocalyptic number.

128759987 is a deficient number, since it is larger than the sum of its proper divisors (1).

128759987 is an equidigital number, since it uses as much as digits as its factorization.

128759987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2540160, while the sum is 56.

The square root of 128759987 is about 11347.2457891772. The cubic root of 128759987 is about 504.9638728526.

The spelling of 128759987 in words is "one hundred twenty-eight million, seven hundred fifty-nine thousand, nine hundred eighty-seven".