78577 has 2 divisors, whose sum is σ = 78578. Its totient is φ = 78576.

The previous prime is 78571. The next prime is 78583. The reversal of 78577 is 77587.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (78571) and next prime (78583).

It can be written as a sum of positive squares in only one way, i.e., 76176 + 2401 = 276^2 + 49^2 .

It is an emirp because it is prime and its reverse (77587) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78577 - 2³ = 78569 is a prime.

It is not a weakly prime, because it can be changed into another prime (78571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39288 + 39289.

It is an arithmetic number, because the mean of its divisors is an integer number (39289).

2⁷⁸⁵⁷⁷ is an apocalyptic number.

It is an amenable number.

78577 is a deficient number, since it is larger than the sum of its proper divisors (1).

78577 is an equidigital number, since it uses as much as digits as its factorization.

78577 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13720, while the sum is 34.

The square root of 78577 is about 280.3158932348. The cubic root of 78577 is about 42.8316838210.

Subtracting from 78577 its reverse (77587), we obtain a triangular number (990 = T₄₄).

The spelling of 78577 in words is "seventy-eight thousand, five hundred seventy-seven".