78737009609 has 2 divisors, whose sum is σ = 78737009610. Its totient is φ = 78737009608.

The previous prime is 78737009591. The next prime is 78737009699. The reversal of 78737009609 is 90690073787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76687455625 + 2049553984 = 276925^2 + 45272^2 .

It is an emirp because it is prime and its reverse (90690073787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78737009609 - 2¹² = 78737005513 is a prime.

It is not a weakly prime, because it can be changed into another prime (78737009699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39368504804 + 39368504805.

It is an arithmetic number, because the mean of its divisors is an integer number (39368504805).

Almost surely, 2^78737009609 is an apocalyptic number.

It is an amenable number.

78737009609 is a deficient number, since it is larger than the sum of its proper divisors (1).

78737009609 is an equidigital number, since it uses as much as digits as its factorization.

78737009609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4000752, while the sum is 56.

The spelling of 78737009609 in words is "seventy-eight billion, seven hundred thirty-seven million, nine thousand, six hundred nine".