77218730 has 8 divisors (see below), whose sum is σ = 138993732. Its totient is φ = 30887488.

The previous prime is 77218727. The next prime is 77218733. The reversal of 77218730 is 3781277.

It is an interprime number because it is at equal distance from previous prime (77218727) and next prime (77218733).

It can be written as a sum of positive squares in 2 ways, for example, as 71250481 + 5968249 = 8441^2 + 2443^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (77218733) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3860927 + ... + 3860946.

Almost surely, 2^77218730 is an apocalyptic number.

77218730 is a deficient number, since it is larger than the sum of its proper divisors (61775002).

77218730 is a wasteful number, since it uses less digits than its factorization.

77218730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7721880.

The product of its (nonzero) digits is 16464, while the sum is 35.

The square root of 77218730 is about 8787.4188474204. The cubic root of 77218730 is about 425.8345401353.

The spelling of 77218730 in words is "seventy-seven million, two hundred eighteen thousand, seven hundred thirty".