78506820 has 360 divisors, whose sum is σ = 305895744. Its totient is φ = 16765056.

The previous prime is 78506819. The next prime is 78506821. The reversal of 78506820 is 2860587.

78506820 is a `hidden beast` number, since 78 + 506 + 82 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (78506819) and next prime (78506821).

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

It is not an unprimeable number, because it can be changed into a prime (78506821) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1825719 + ... + 1825761.

Almost surely, 2^78506820 is an apocalyptic number.

78506820 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78506820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152947872).

78506820 is an abundant number, since it is smaller than the sum of its proper divisors (227388924).

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

78506820 is a wasteful number, since it uses less digits than its factorization.

78506820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 78506820 is about 8860.4074398416. The cubic root of 78506820 is about 428.1892850704.

The spelling of 78506820 in words is "seventy-eight million, five hundred six thousand, eight hundred twenty".