16978743361 has 4 divisors (see below), whose sum is σ = 17564217300. Its totient is φ = 16393269424.

The previous prime is 16978743347. The next prime is 16978743443. The reversal of 16978743361 is 16334787961.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4534002225 + 12444741136 = 67335^2 + 111556^2 .

It is a cyclic number.

It is not a de Polignac number, because 16978743361 - 2¹⁷ = 16978612289 is a prime.

It is a super-2 number, since 2×16978743361² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16978743161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 292736926 + ... + 292736983.

It is an arithmetic number, because the mean of its divisors is an integer number (4391054325).

Almost surely, 2^16978743361 is an apocalyptic number.

It is an amenable number.

16978743361 is a deficient number, since it is larger than the sum of its proper divisors (585473939).

16978743361 is an equidigital number, since it uses as much as digits as its factorization.

16978743361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 585473938.

The product of its digits is 4572288, while the sum is 55.

The spelling of 16978743361 in words is "sixteen billion, nine hundred seventy-eight million, seven hundred forty-three thousand, three hundred sixty-one".