78442228 has 12 divisors (see below), whose sum is σ = 137348932. Its totient is φ = 39199680.

The previous prime is 78442207. The next prime is 78442229. The reversal of 78442228 is 82224487.

It can be written as a sum of positive squares in 2 ways, for example, as 29833444 + 48608784 = 5462^2 + 6972^2 .

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78442229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5176 + ... + 13552.

Almost surely, 2^78442228 is an apocalyptic number.

It is an amenable number.

78442228 is a deficient number, since it is larger than the sum of its proper divisors (58906704).

78442228 is a wasteful number, since it uses less digits than its factorization.

78442228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10722 (or 10720 counting only the distinct ones).

The product of its digits is 57344, while the sum is 37.

The square root of 78442228 is about 8856.7617106931. The cubic root of 78442228 is about 428.0718210041.

The spelling of 78442228 in words is "seventy-eight million, four hundred forty-two thousand, two hundred twenty-eight".