78820647 has 8 divisors (see below), whose sum is σ = 106114944. Its totient is φ = 52036728.

The previous prime is 78820639. The next prime is 78820649. The reversal of 78820647 is 74602887.

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

It is not a de Polignac number, because 78820647 - 2³ = 78820639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78820599 and 78820608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78820649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127233 + ... + 127850.

It is an arithmetic number, because the mean of its divisors is an integer number (13264368).

Almost surely, 2^78820647 is an apocalyptic number.

78820647 is a deficient number, since it is larger than the sum of its proper divisors (27294297).

78820647 is a wasteful number, since it uses less digits than its factorization.

78820647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255189.

The product of its (nonzero) digits is 150528, while the sum is 42.

The square root of 78820647 is about 8878.0992898255. The cubic root of 78820647 is about 428.7590814261.

The spelling of 78820647 in words is "seventy-eight million, eight hundred twenty thousand, six hundred forty-seven".