1328406421 has 2 divisors, whose sum is σ = 1328406422. Its totient is φ = 1328406420.

The previous prime is 1328406403. The next prime is 1328406433. The reversal of 1328406421 is 1246048231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 704106225 + 624300196 = 26535^2 + 24986^2 .

It is a cyclic number.

It is not a de Polignac number, because 1328406421 - 2⁹ = 1328405909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1328406481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 664203210 + 664203211.

It is an arithmetic number, because the mean of its divisors is an integer number (664203211).

Almost surely, 2^1328406421 is an apocalyptic number.

It is an amenable number.

1328406421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1328406421 is an equidigital number, since it uses as much as digits as its factorization.

1328406421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 1328406421 is about 36447.3102025376. The cubic root of 1328406421 is about 1099.2850508438.

The spelling of 1328406421 in words is "one billion, three hundred twenty-eight million, four hundred six thousand, four hundred twenty-one".