78820078 has 4 divisors (see below), whose sum is σ = 118230120. Its totient is φ = 39410038.

The previous prime is 78820069. The next prime is 78820087. The reversal of 78820078 is 87002887.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87002887 = 3391 ⋅25657.

It is an interprime number because it is at equal distance from previous prime (78820069) and next prime (78820087).

It is a self number, because there is not a number n which added to its sum of digits gives 78820078.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19705018 + ... + 19705021.

It is an arithmetic number, because the mean of its divisors is an integer number (29557530).

Almost surely, 2^78820078 is an apocalyptic number.

78820078 is a deficient number, since it is larger than the sum of its proper divisors (39410042).

78820078 is a wasteful number, since it uses less digits than its factorization.

78820078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39410041.

The product of its (nonzero) digits is 50176, while the sum is 40.

The square root of 78820078 is about 8878.0672446203. The cubic root of 78820078 is about 428.7580496977.

The spelling of 78820078 in words is "seventy-eight million, eight hundred twenty thousand, seventy-eight".