78659645 has 4 divisors (see below), whose sum is σ = 94391580. Its totient is φ = 62927712.

The previous prime is 78659641. The next prime is 78659653. The reversal of 78659645 is 54695687.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54695687 = 31 ⋅1764377.

It can be written as a sum of positive squares in 2 ways, for example, as 28504921 + 50154724 = 5339^2 + 7082^2 .

It is a cyclic number.

It is not a de Polignac number, because 78659645 - 2² = 78659641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78659593 and 78659602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78659641) 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, 7865960 + ... + 7865969.

It is an arithmetic number, because the mean of its divisors is an integer number (23597895).

Almost surely, 2^78659645 is an apocalyptic number.

It is an amenable number.

78659645 is a deficient number, since it is larger than the sum of its proper divisors (15731935).

78659645 is a wasteful number, since it uses less digits than its factorization.

78659645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15731934.

The product of its digits is 1814400, while the sum is 50.

The square root of 78659645 is about 8869.0272860106. The cubic root of 78659645 is about 428.4669493200.

The spelling of 78659645 in words is "seventy-eight million, six hundred fifty-nine thousand, six hundred forty-five".