78420218 has 16 divisors (see below), whose sum is σ = 127448640. Its totient is φ = 36044736.

The previous prime is 78420203. The next prime is 78420227. The reversal of 78420218 is 81202487.

It is a super-2 number, since 2×78420218² = 12299461182335048, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25358 + ... + 28281.

It is an arithmetic number, because the mean of its divisors is an integer number (7965540).

Almost surely, 2^78420218 is an apocalyptic number.

78420218 is a deficient number, since it is larger than the sum of its proper divisors (49028422).

78420218 is a wasteful number, since it uses less digits than its factorization.

78420218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53701.

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 78420218 is about 8855.5190700489. The cubic root of 78420218 is about 428.0317798919.

The spelling of 78420218 in words is "seventy-eight million, four hundred twenty thousand, two hundred eighteen".