78321085 has 4 divisors (see below), whose sum is σ = 93985308. Its totient is φ = 62656864.

The previous prime is 78321077. The next prime is 78321107. The reversal of 78321085 is 58012387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58012387 = 277 ⋅209431.

It can be written as a sum of positive squares in 2 ways, for example, as 8213956 + 70107129 = 2866^2 + 8373^2 .

It is a cyclic number.

It is not a de Polignac number, because 78321085 - 2³ = 78321077 is a prime.

It is a super-2 number, since 2×78321085² = 12268384711154450, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78321085.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7832104 + ... + 7832113.

It is an arithmetic number, because the mean of its divisors is an integer number (23496327).

Almost surely, 2^78321085 is an apocalyptic number.

It is an amenable number.

78321085 is a deficient number, since it is larger than the sum of its proper divisors (15664223).

78321085 is a wasteful number, since it uses less digits than its factorization.

78321085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15664222.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 78321085 is about 8849.9200561361. The cubic root of 78321085 is about 427.8513418709.

The spelling of 78321085 in words is "seventy-eight million, three hundred twenty-one thousand, eighty-five".