16519439378 has 18 divisors (see below), whose sum is σ = 26835709077. Its totient is φ = 7623266040.

The previous prime is 16519439369. The next prime is 16519439383. The reversal of 16519439378 is 87393491561.

It can be written as a sum of positive squares in 2 ways, for example, as 14124609409 + 2394829969 = 118847^2 + 48937^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=90883.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2359463 + ... + 2366453.

Almost surely, 2^16519439378 is an apocalyptic number.

16519439378 is a deficient number, since it is larger than the sum of its proper divisors (10316269699).

16519439378 is an frugal number, since it uses more digits than its factorization.

16519439378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14010 (or 7006 counting only the distinct ones).

The product of its digits is 4898880, while the sum is 56.

The spelling of 16519439378 in words is "sixteen billion, five hundred nineteen million, four hundred thirty-nine thousand, three hundred seventy-eight".