1321409 has 2 divisors, whose sum is σ = 1321410. Its totient is φ = 1321408.

The previous prime is 1321399. The next prime is 1321417. The reversal of 1321409 is 9041231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1149184 + 172225 = 1072^2 + 415^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321409 is a prime.

It is a super-2 number, since 2×1321409² = 3492243490562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660704 + 660705.

It is an arithmetic number, because the mean of its divisors is an integer number (660705).

2^1321409 is an apocalyptic number.

It is an amenable number.

1321409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321409 is an equidigital number, since it uses as much as digits as its factorization.

1321409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 1321409 is about 1149.5255543049. The cubic root of 1321409 is about 109.7351479393.

The spelling of 1321409 in words is "one million, three hundred twenty-one thousand, four hundred nine".