78216812 has 12 divisors (see below), whose sum is σ = 136995096. Its totient is φ = 39075360.

The previous prime is 78216781. The next prime is 78216839. The reversal of 78216812 is 21861287.

It is a super-2 number, since 2×78216812² = 12235739358886688, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2489 + ... + 12752.

It is an arithmetic number, because the mean of its divisors is an integer number (11416258).

Almost surely, 2^78216812 is an apocalyptic number.

It is an amenable number.

78216812 is a deficient number, since it is larger than the sum of its proper divisors (58778284).

78216812 is a wasteful number, since it uses less digits than its factorization.

78216812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16528 (or 16526 counting only the distinct ones).

The product of its digits is 10752, while the sum is 35.

The square root of 78216812 is about 8844.0269108591. The cubic root of 78216812 is about 427.6613838440.

The spelling of 78216812 in words is "seventy-eight million, two hundred sixteen thousand, eight hundred twelve".