78216804 has 36 divisors (see below), whose sum is σ = 198621696. Its totient is φ = 25952688.

The previous prime is 78216781. The next prime is 78216839. The reversal of 78216804 is 40861287.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×78216804² = 12235736855948832, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3157 + ... + 12899.

Almost surely, 2^78216804 is an apocalyptic number.

It is an amenable number.

78216804 is an abundant number, since it is smaller than the sum of its proper divisors (120404892).

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

78216804 is a wasteful number, since it uses less digits than its factorization.

78216804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9976 (or 9971 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 78216804 is about 8844.0264585764. The cubic root of 78216804 is about 427.6613692636.

The spelling of 78216804 in words is "seventy-eight million, two hundred sixteen thousand, eight hundred four".