16678025578 has 4 divisors (see below), whose sum is σ = 25017038370. Its totient is φ = 8339012788.

The previous prime is 16678025557. The next prime is 16678025587. The reversal of 16678025578 is 87552087661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87552087661 = 23 ⋅3806612507.

It can be written as a sum of positive squares in only one way, i.e., 11804170609 + 4873854969 = 108647^2 + 69813^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4169506393 + ... + 4169506396.

Almost surely, 2^16678025578 is an apocalyptic number.

16678025578 is a deficient number, since it is larger than the sum of its proper divisors (8339012792).

16678025578 is an equidigital number, since it uses as much as digits as its factorization.

16678025578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8339012791.

The product of its (nonzero) digits is 5644800, while the sum is 55.

The spelling of 16678025578 in words is "sixteen billion, six hundred seventy-eight million, twenty-five thousand, five hundred seventy-eight".