78217800 has 48 divisors (see below), whose sum is σ = 242477040. Its totient is φ = 20857920.

The previous prime is 78217781. The next prime is 78217801. The reversal of 78217800 is 871287.

It is a super-2 number, since 2×78217800² = 12236048473680000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78217801) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64582 + ... + 65781.

It is an arithmetic number, because the mean of its divisors is an integer number (5051605).

Almost surely, 2^78217800 is an apocalyptic number.

It is an amenable number.

78217800 is an abundant number, since it is smaller than the sum of its proper divisors (164259240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78217800 is a wasteful number, since it uses less digits than its factorization.

78217800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130382 (or 130373 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 33.

The square root of 78217800 is about 8844.0827675910. The cubic root of 78217800 is about 427.6631845126.

The spelling of 78217800 in words is "seventy-eight million, two hundred seventeen thousand, eight hundred".