128138893 has 2 divisors, whose sum is σ = 128138894. Its totient is φ = 128138892.

The previous prime is 128138891. The next prime is 128138929. The reversal of 128138893 is 398831821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78535044 + 49603849 = 8862^2 + 7043^2 .

It is a cyclic number.

It is not a de Polignac number, because 128138893 - 2¹ = 128138891 is a prime.

Together with 128138891, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128138891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64069446 + 64069447.

It is an arithmetic number, because the mean of its divisors is an integer number (64069447).

Almost surely, 2^128138893 is an apocalyptic number.

It is an amenable number.

128138893 is a deficient number, since it is larger than the sum of its proper divisors (1).

128138893 is an equidigital number, since it uses as much as digits as its factorization.

128138893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 43.

The square root of 128138893 is about 11319.8450961133. The cubic root of 128138893 is about 504.1506397048.

The spelling of 128138893 in words is "one hundred twenty-eight million, one hundred thirty-eight thousand, eight hundred ninety-three".