77939486309 has 2 divisors, whose sum is σ = 77939486310. Its totient is φ = 77939486308.

The previous prime is 77939486279. The next prime is 77939486333. The reversal of 77939486309 is 90368493977.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61527314209 + 16412172100 = 248047^2 + 128110^2 .

It is a cyclic number.

It is not a de Polignac number, because 77939486309 - 2¹² = 77939482213 is a prime.

It is a super-2 number, since 2×77939486309² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77939486369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38969743154 + 38969743155.

It is an arithmetic number, because the mean of its divisors is an integer number (38969743155).

Almost surely, 2^77939486309 is an apocalyptic number.

It is an amenable number.

77939486309 is a deficient number, since it is larger than the sum of its proper divisors (1).

77939486309 is an equidigital number, since it uses as much as digits as its factorization.

77939486309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61725888, while the sum is 65.

The spelling of 77939486309 in words is "seventy-seven billion, nine hundred thirty-nine million, four hundred eighty-six thousand, three hundred nine".