1242320161 has 2 divisors, whose sum is σ = 1242320162. Its totient is φ = 1242320160.

The previous prime is 1242320153. The next prime is 1242320173. The reversal of 1242320161 is 1610232421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1242139536 + 180625 = 35244^2 + 425^2 .

It is a cyclic number.

It is not a de Polignac number, because 1242320161 - 2³ = 1242320153 is a prime.

It is not a weakly prime, because it can be changed into another prime (1242320561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621160080 + 621160081.

It is an arithmetic number, because the mean of its divisors is an integer number (621160081).

Almost surely, 2^1242320161 is an apocalyptic number.

It is an amenable number.

1242320161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242320161 is an equidigital number, since it uses as much as digits as its factorization.

1242320161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 1242320161 is about 35246.5623997575. The cubic root of 1242320161 is about 1075.0067166698.

Adding to 1242320161 its reverse (1610232421), we get a palindrome (2852552582).

The spelling of 1242320161 in words is "one billion, two hundred forty-two million, three hundred twenty thousand, one hundred sixty-one".