128102321 has 2 divisors, whose sum is σ = 128102322. Its totient is φ = 128102320.

The previous prime is 128102297. The next prime is 128102339. The reversal of 128102321 is 123201821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 124567921 + 3534400 = 11161^2 + 1880^2 .

It is an emirp because it is prime and its reverse (123201821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128102321 - 2²² = 123908017 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 128102293 and 128102302.

It is not a weakly prime, because it can be changed into another prime (128105321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64051160 + 64051161.

It is an arithmetic number, because the mean of its divisors is an integer number (64051161).

Almost surely, 2^128102321 is an apocalyptic number.

It is an amenable number.

128102321 is a deficient number, since it is larger than the sum of its proper divisors (1).

128102321 is an equidigital number, since it uses as much as digits as its factorization.

128102321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 128102321 is about 11318.2295877050. The cubic root of 128102321 is about 504.1026720890.

The spelling of 128102321 in words is "one hundred twenty-eight million, one hundred two thousand, three hundred twenty-one".