78659969 has 8 divisors (see below), whose sum is σ = 83476008. Its totient is φ = 73864960.

The previous prime is 78659963. The next prime is 78660011. The reversal of 78659969 is 96995687.

It can be written as a sum of positive squares in 4 ways, for example, as 9985600 + 68674369 = 3160^2 + 8287^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78659969 is a prime.

It is a super-2 number, since 2×78659969² = 12374781446161922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78659963) 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, 2819 + ... + 12855.

It is an arithmetic number, because the mean of its divisors is an integer number (10434501).

Almost surely, 2^78659969 is an apocalyptic number.

It is an amenable number.

78659969 is a deficient number, since it is larger than the sum of its proper divisors (4816039).

78659969 is a wasteful number, since it uses less digits than its factorization.

78659969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10515.

The product of its digits is 7348320, while the sum is 59.

The square root of 78659969 is about 8869.0455518054. The cubic root of 78659969 is about 428.4675376060.

The spelling of 78659969 in words is "seventy-eight million, six hundred fifty-nine thousand, nine hundred sixty-nine".