78289278 has 8 divisors (see below), whose sum is σ = 156578568. Its totient is φ = 26096424.

The previous prime is 78289273. The next prime is 78289297. The reversal of 78289278 is 87298287.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

78289278 is an admirable number.

It is a super-2 number, since 2×78289278² = 12258422099522568, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78289278.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78289273) 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, 6524101 + ... + 6524112.

It is an arithmetic number, because the mean of its divisors is an integer number (19572321).

Almost surely, 2^78289278 is an apocalyptic number.

78289278 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

78289278 is a wasteful number, since it uses less digits than its factorization.

78289278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13048218.

The product of its digits is 903168, while the sum is 51.

The square root of 78289278 is about 8848.1228517692. The cubic root of 78289278 is about 427.7934157486.

Subtracting 78289278 from its reverse (87298287), we obtain a palindrome (9009009).

The spelling of 78289278 in words is "seventy-eight million, two hundred eighty-nine thousand, two hundred seventy-eight".