1324521661 has 2 divisors, whose sum is σ = 1324521662. Its totient is φ = 1324521660.

The previous prime is 1324521607. The next prime is 1324521683. The reversal of 1324521661 is 1661254231.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1200622500 + 123899161 = 34650^2 + 11131^2 .

It is a cyclic number.

It is not a de Polignac number, because 1324521661 - 2⁷ = 1324521533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1324521691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 662260830 + 662260831.

It is an arithmetic number, because the mean of its divisors is an integer number (662260831).

Almost surely, 2^1324521661 is an apocalyptic number.

It is an amenable number.

1324521661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1324521661 is an equidigital number, since it uses as much as digits as its factorization.

1324521661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 31.

The square root of 1324521661 is about 36393.9783618114. The cubic root of 1324521661 is about 1098.2124302682.

Adding to 1324521661 its reverse (1661254231), we get a palindrome (2985775892).

The spelling of 1324521661 in words is "one billion, three hundred twenty-four million, five hundred twenty-one thousand, six hundred sixty-one".