78806709 has 8 divisors (see below), whose sum is σ = 116750720. Its totient is φ = 52537788.

The previous prime is 78806683. The next prime is 78806729. The reversal of 78806709 is 90760887.

It is not a de Polignac number, because 78806709 - 2⁹ = 78806197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78806729) 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, 1459357 + ... + 1459410.

It is an arithmetic number, because the mean of its divisors is an integer number (14593840).

Almost surely, 2^78806709 is an apocalyptic number.

It is an amenable number.

78806709 is a deficient number, since it is larger than the sum of its proper divisors (37944011).

78806709 is a wasteful number, since it uses less digits than its factorization.

78806709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2918776 (or 2918770 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The square root of 78806709 is about 8877.3142898063. The cubic root of 78806709 is about 428.7338071840.

The spelling of 78806709 in words is "seventy-eight million, eight hundred six thousand, seven hundred nine".