77369681 has 2 divisors, whose sum is σ = 77369682. Its totient is φ = 77369680.

The previous prime is 77369641. The next prime is 77369683. The reversal of 77369681 is 18696377.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76387600 + 982081 = 8740^2 + 991^2 .

It is a cyclic number.

It is not a de Polignac number, because 77369681 - 2¹⁰ = 77368657 is a prime.

It is a super-2 number, since 2×77369681² = 11972135076083522, which contains 22 as substring.

Together with 77369683, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77369683) 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, 38684840 + 38684841.

It is an arithmetic number, because the mean of its divisors is an integer number (38684841).

Almost surely, 2^77369681 is an apocalyptic number.

It is an amenable number.

77369681 is a deficient number, since it is larger than the sum of its proper divisors (1).

77369681 is an equidigital number, since it uses as much as digits as its factorization.

77369681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 381024, while the sum is 47.

The square root of 77369681 is about 8796.0036948605. The cubic root of 77369681 is about 426.1118403408. Note that the first 3 decimals are identical.

The spelling of 77369681 in words is "seventy-seven million, three hundred sixty-nine thousand, six hundred eighty-one".