78550643 has 4 divisors (see below), whose sum is σ = 79169280. Its totient is φ = 77932008.

The previous prime is 78550627. The next prime is 78550651. The reversal of 78550643 is 34605587.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78550643 - 2⁴ = 78550627 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78550597 and 78550606.

It is not an unprimeable number, because it can be changed into a prime (78550343) 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, 309128 + ... + 309381.

It is an arithmetic number, because the mean of its divisors is an integer number (19792320).

Almost surely, 2^78550643 is an apocalyptic number.

78550643 is a deficient number, since it is larger than the sum of its proper divisors (618637).

78550643 is a wasteful number, since it uses less digits than its factorization.

78550643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618636.

The product of its (nonzero) digits is 100800, while the sum is 38.

The square root of 78550643 is about 8862.8800623725. The cubic root of 78550643 is about 428.2689428998.

The spelling of 78550643 in words is "seventy-eight million, five hundred fifty thousand, six hundred forty-three".