77390609 has 2 divisors, whose sum is σ = 77390610. Its totient is φ = 77390608.

The previous prime is 77390603. The next prime is 77390617. The reversal of 77390609 is 90609377.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59985025 + 17405584 = 7745^2 + 4172^2 .

It is an emirp because it is prime and its reverse (90609377) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77390609 - 2²⁰ = 76342033 is a prime.

It is a super-2 number, since 2×77390609² = 11978612722781762, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (77390603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38695304 + 38695305.

It is an arithmetic number, because the mean of its divisors is an integer number (38695305).

Almost surely, 2^77390609 is an apocalyptic number.

It is an amenable number.

77390609 is a deficient number, since it is larger than the sum of its proper divisors (1).

77390609 is an equidigital number, since it uses as much as digits as its factorization.

77390609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 71442, while the sum is 41.

The square root of 77390609 is about 8797.1932455755. The cubic root of 77390609 is about 426.1502570459.

The spelling of 77390609 in words is "seventy-seven million, three hundred ninety thousand, six hundred nine".