78224578 has 4 divisors (see below), whose sum is σ = 117336870. Its totient is φ = 39112288.

The previous prime is 78224569. The next prime is 78224579. The reversal of 78224578 is 87542287.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87542287 = 7 ⋅12506041.

It can be written as a sum of positive squares in only one way, i.e., 74701449 + 3523129 = 8643^2 + 1877^2 .

It is a super-2 number, since 2×78224578² = 12238169206556168, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78224579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19556143 + ... + 19556146.

Almost surely, 2^78224578 is an apocalyptic number.

78224578 is a deficient number, since it is larger than the sum of its proper divisors (39112292).

78224578 is a wasteful number, since it uses less digits than its factorization.

78224578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39112291.

The product of its digits is 250880, while the sum is 43.

The square root of 78224578 is about 8844.4659533518. The cubic root of 78224578 is about 427.6755372734.

The spelling of 78224578 in words is "seventy-eight million, two hundred twenty-four thousand, five hundred seventy-eight".