78220072 has 48 divisors (see below), whose sum is σ = 175251060. Its totient is φ = 32610816.

The previous prime is 78220063. The next prime is 78220127. The reversal of 78220072 is 27002287.

It can be written as a sum of positive squares in 2 ways, for example, as 59505796 + 18714276 = 7714^2 + 4326^2 .

It is a super-2 number, since 2×78220072² = 12236759327370368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a self number, because there is not a number n which added to its sum of digits gives 78220072.

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 11 ways as a sum of consecutive naturals, for example, 11808 + ... + 17200.

Almost surely, 2^78220072 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 78220072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87625530).

78220072 is an abundant number, since it is smaller than the sum of its proper divisors (97030988).

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

78220072 is a wasteful number, since it uses less digits than its factorization.

78220072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5450 (or 5439 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 28.

The square root of 78220072 is about 8844.2112141219. The cubic root of 78220072 is about 427.6673252638.

The spelling of 78220072 in words is "seventy-eight million, two hundred twenty thousand, seventy-two".