78646865 has 8 divisors (see below), whose sum is σ = 102955968. Its totient is φ = 57197680.

The previous prime is 78646861. The next prime is 78646889. The reversal of 78646865 is 56864687.

It is a happy number.

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

It is not a de Polignac number, because 78646865 - 2² = 78646861 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78646861) 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, 714917 + ... + 715026.

It is an arithmetic number, because the mean of its divisors is an integer number (12869496).

Almost surely, 2^78646865 is an apocalyptic number.

It is an amenable number.

78646865 is a deficient number, since it is larger than the sum of its proper divisors (24309103).

78646865 is a wasteful number, since it uses less digits than its factorization.

78646865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1429959.

The product of its digits is 1935360, while the sum is 50.

The square root of 78646865 is about 8868.3067718703. The cubic root of 78646865 is about 428.4437434173.

The spelling of 78646865 in words is "seventy-eight million, six hundred forty-six thousand, eight hundred sixty-five".