77438239 has 2 divisors, whose sum is σ = 77438240. Its totient is φ = 77438238.

The previous prime is 77438233. The next prime is 77438293. The reversal of 77438239 is 93283477.

Together with next prime (77438293) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77438239 - 2¹³ = 77430047 is a prime.

It is a super-2 number, since 2×77438239² = 11993361718842242, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 77438195 and 77438204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77438233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38719119 + 38719120.

It is an arithmetic number, because the mean of its divisors is an integer number (38719120).

Almost surely, 2^77438239 is an apocalyptic number.

77438239 is a deficient number, since it is larger than the sum of its proper divisors (1).

77438239 is an equidigital number, since it uses as much as digits as its factorization.

77438239 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 43.

The square root of 77438239 is about 8799.8999426130. The cubic root of 77438239 is about 426.2376637498.

It can be divided in two parts, 77438 and 239, that added together give a palindrome (77677).

The spelling of 77438239 in words is "seventy-seven million, four hundred thirty-eight thousand, two hundred thirty-nine".