78822720 has 140 divisors (see below), whose sum is σ = 280478484. Its totient is φ = 21012480.

The previous prime is 78822701. The next prime is 78822721. The reversal of 78822720 is 2722887.

It can be written as a sum of positive squares in 2 ways, for example, as 58247424 + 20575296 = 7632^2 + 4536^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78822721) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 24400 + ... + 27440.

Almost surely, 2^78822720 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 78822720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140239242).

78822720 is an abundant number, since it is smaller than the sum of its proper divisors (201655764).

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

78822720 is a wasteful number, since it uses less digits than its factorization.

78822720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3070 (or 3051 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 36.

The square root of 78822720 is about 8878.2160370200. The cubic root of 78822720 is about 428.7628402119.

The spelling of 78822720 in words is "seventy-eight million, eight hundred twenty-two thousand, seven hundred twenty".