67639009 has 2 divisors, whose sum is σ = 67639010. Its totient is φ = 67639008.

The previous prime is 67639007. The next prime is 67639027. The reversal of 67639009 is 90093676.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47568609 + 20070400 = 6897^2 + 4480^2 .

It is a cyclic number.

It is not a de Polignac number, because 67639009 - 2¹ = 67639007 is a prime.

Together with 67639007, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (67639001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33819504 + 33819505.

It is an arithmetic number, because the mean of its divisors is an integer number (33819505).

Almost surely, 2^67639009 is an apocalyptic number.

It is an amenable number.

67639009 is a deficient number, since it is larger than the sum of its proper divisors (1).

67639009 is an equidigital number, since it uses as much as digits as its factorization.

67639009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61236, while the sum is 40.

The square root of 67639009 is about 8224.2938298677. The cubic root of 67639009 is about 407.4419534166.

The spelling of 67639009 in words is "sixty-seven million, six hundred thirty-nine thousand, nine".