67642321 has 2 divisors, whose sum is σ = 67642322. Its totient is φ = 67642320.

The previous prime is 67642319. The next prime is 67642331. The reversal of 67642321 is 12324676.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66601921 + 1040400 = 8161^2 + 1020^2 .

It is a cyclic number.

It is not a de Polignac number, because 67642321 - 2¹ = 67642319 is a prime.

Together with 67642319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (67642331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33821160 + 33821161.

It is an arithmetic number, because the mean of its divisors is an integer number (33821161).

Almost surely, 2^67642321 is an apocalyptic number.

It is an amenable number.

67642321 is a deficient number, since it is larger than the sum of its proper divisors (1).

67642321 is an equidigital number, since it uses as much as digits as its factorization.

67642321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 31.

The square root of 67642321 is about 8224.4951820765. The cubic root of 67642321 is about 407.4486035521.

Adding to 67642321 its reverse (12324676), we get a palindrome (79966997).

The spelling of 67642321 in words is "sixty-seven million, six hundred forty-two thousand, three hundred twenty-one".