1328905121 has 2 divisors, whose sum is σ = 1328905122. Its totient is φ = 1328905120.

The previous prime is 1328905111. The next prime is 1328905157. The reversal of 1328905121 is 1215098231.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1264584721 + 64320400 = 35561^2 + 8020^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1328905121 is a prime.

It is not a weakly prime, because it can be changed into another prime (1328905111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 664452560 + 664452561.

It is an arithmetic number, because the mean of its divisors is an integer number (664452561).

Almost surely, 2^1328905121 is an apocalyptic number.

It is an amenable number.

1328905121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1328905121 is an equidigital number, since it uses as much as digits as its factorization.

1328905121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 1328905121 is about 36454.1509433425. The cubic root of 1328905121 is about 1099.4225953127.

The spelling of 1328905121 in words is "one billion, three hundred twenty-eight million, nine hundred five thousand, one hundred twenty-one".