78326820 has 288 divisors, whose sum is σ = 297198720. Its totient is φ = 16404480.

The previous prime is 78326789. The next prime is 78326839. The reversal of 78326820 is 2862387.

It is a happy number.

It is a super-2 number, since 2×78326820² = 12270181462624800, 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 pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 437491 + ... + 437669.

It is an arithmetic number, because the mean of its divisors is an integer number (1031940).

Almost surely, 2^78326820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78326820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148599360).

78326820 is an abundant number, since it is smaller than the sum of its proper divisors (218871900).

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

78326820 is a wasteful number, since it uses less digits than its factorization.

78326820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 78326820 is about 8850.2440644312. The cubic root of 78326820 is about 427.8617846423.

The spelling of 78326820 in words is "seventy-eight million, three hundred twenty-six thousand, eight hundred twenty".