2198728768865 has 4 divisors (see below), whose sum is σ = 2638474522644. Its totient is φ = 1758983015088.

The previous prime is 2198728768829. The next prime is 2198728768883. The reversal of 2198728768865 is 5688678278912.

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 442276871521 + 1756451897344 = 665039^2 + 1325312^2 .

It is a cyclic number.

It is not a de Polignac number, because 2198728768865 - 2¹² = 2198728764769 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219872876882 + ... + 219872876891.

It is an arithmetic number, because the mean of its divisors is an integer number (659618630661).

Almost surely, 2^{2198728768865} is an apocalyptic number.

It is an amenable number.

2198728768865 is a deficient number, since it is larger than the sum of its proper divisors (439745753779).

2198728768865 is an equidigital number, since it uses as much as digits as its factorization.

2198728768865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439745753778.

The product of its digits is 1300561920, while the sum is 77.

The spelling of 2198728768865 in words is "two trillion, one hundred ninety-eight billion, seven hundred twenty-eight million, seven hundred sixty-eight thousand, eight hundred sixty-five".