77218 has 4 divisors (see below), whose sum is σ = 115830. Its totient is φ = 38608.

The previous prime is 77213. The next prime is 77237. The reversal of 77218 is 81277.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 71289 + 5929 = 267^2 + 77^2 .

It is a junction number, because it is equal to n+sod(n) for n = 77192 and 77201.

It is not an unprimeable number, because it can be changed into a prime (77213) by changing a digit.

77218 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19303 + ... + 19306.

2⁷⁷²¹⁸ is an apocalyptic number.

77218 is a deficient number, since it is larger than the sum of its proper divisors (38612).

77218 is a wasteful number, since it uses less digits than its factorization.

77218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38611.

The product of its digits is 784, while the sum is 25.

The square root of 77218 is about 277.8812696099. The cubic root of 77218 is about 42.5833198232.

It can be divided in two parts, 7 and 7218, that added together give a square (7225 = 85²).

The spelling of 77218 in words is "seventy-seven thousand, two hundred eighteen".