77427839 has 2 divisors, whose sum is σ = 77427840. Its totient is φ = 77427838.

The previous prime is 77427829. The next prime is 77427853. The reversal of 77427839 is 93872477.

It is a weak prime.

It is an emirp because it is prime and its reverse (93872477) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77427839 - 2¹² = 77423743 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 77427793 and 77427802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77427829) 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, 38713919 + 38713920.

It is an arithmetic number, because the mean of its divisors is an integer number (38713920).

Almost surely, 2^77427839 is an apocalyptic number.

77427839 is a deficient number, since it is larger than the sum of its proper divisors (1).

77427839 is an equidigital number, since it uses as much as digits as its factorization.

77427839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 592704, while the sum is 47.

The square root of 77427839 is about 8799.3090069619. The cubic root of 77427839 is about 426.2185815744.

The spelling of 77427839 in words is "seventy-seven million, four hundred twenty-seven thousand, eight hundred thirty-nine".