78685321 has 16 divisors (see below), whose sum is σ = 92731968. Its totient is φ = 65822400.

The previous prime is 78685319. The next prime is 78685349. The reversal of 78685321 is 12358687.

It is a cyclic number.

It is not a de Polignac number, because 78685321 - 2¹ = 78685319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78685301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59550 + ... + 60856.

It is an arithmetic number, because the mean of its divisors is an integer number (5795748).

Almost surely, 2^78685321 is an apocalyptic number.

It is an amenable number.

78685321 is a deficient number, since it is larger than the sum of its proper divisors (14046647).

78685321 is a wasteful number, since it uses less digits than its factorization.

78685321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1752.

The product of its digits is 80640, while the sum is 40.

The square root of 78685321 is about 8870.4746772650. The cubic root of 78685321 is about 428.5135641612.

The spelling of 78685321 in words is "seventy-eight million, six hundred eighty-five thousand, three hundred twenty-one".