77670709 has 2 divisors, whose sum is σ = 77670710. Its totient is φ = 77670708.

The previous prime is 77670647. The next prime is 77670731. The reversal of 77670709 is 90707677.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53611684 + 24059025 = 7322^2 + 4905^2 .

It is an emirp because it is prime and its reverse (90707677) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77670709 - 2⁷ = 77670581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77670809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38835354 + 38835355.

It is an arithmetic number, because the mean of its divisors is an integer number (38835355).

Almost surely, 2^77670709 is an apocalyptic number.

It is an amenable number.

77670709 is a deficient number, since it is larger than the sum of its proper divisors (1).

77670709 is an equidigital number, since it uses as much as digits as its factorization.

77670709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 129654, while the sum is 43.

The square root of 77670709 is about 8813.0987172504. The cubic root of 77670709 is about 426.6637602205.

The spelling of 77670709 in words is "seventy-seven million, six hundred seventy thousand, seven hundred nine".