78338218609 has 16 divisors (see below), whose sum is σ = 90609012736. Its totient is φ = 66341721600.

The previous prime is 78338218601. The next prime is 78338218613. The reversal of 78338218609 is 90681283387.

It is not a de Polignac number, because 78338218609 - 2³ = 78338218601 is a prime.

It is a super-2 number, since 2×78338218609² (a number of 23 digits) 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 78338218609.

It is not an unprimeable number, because it can be changed into a prime (78338218601) 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, 31429 + ... + 397069.

It is an arithmetic number, because the mean of its divisors is an integer number (5663063296).

Almost surely, 2^78338218609 is an apocalyptic number.

It is an amenable number.

78338218609 is a deficient number, since it is larger than the sum of its proper divisors (12270794127).

78338218609 is a wasteful number, since it uses less digits than its factorization.

78338218609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366016.

The product of its (nonzero) digits is 3483648, while the sum is 55.

The spelling of 78338218609 in words is "seventy-eight billion, three hundred thirty-eight million, two hundred eighteen thousand, six hundred nine".