77090979209 has 2 divisors, whose sum is σ = 77090979210. Its totient is φ = 77090979208.

The previous prime is 77090979157. The next prime is 77090979263. The reversal of 77090979209 is 90297909077.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58121977225 + 18969001984 = 241085^2 + 137728^2 .

It is a cyclic number.

It is not a de Polignac number, because 77090979209 - 2¹² = 77090975113 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (77090979289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38545489604 + 38545489605.

It is an arithmetic number, because the mean of its divisors is an integer number (38545489605).

Almost surely, 2^77090979209 is an apocalyptic number.

It is an amenable number.

77090979209 is a deficient number, since it is larger than the sum of its proper divisors (1).

77090979209 is an equidigital number, since it uses as much as digits as its factorization.

77090979209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4500846, while the sum is 59.

The spelling of 77090979209 in words is "seventy-seven billion, ninety million, nine hundred seventy-nine thousand, two hundred nine".