221678048591999 has 4 divisors (see below), whose sum is σ = 223296136538064. Its totient is φ = 220059960645936.

The previous prime is 221678048591963. The next prime is 221678048592067. The reversal of 221678048591999 is 999195840876122.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221678048591999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221678048591599) 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, 809043972827 + ... + 809043973100.

It is an arithmetic number, because the mean of its divisors is an integer number (55824034134516).

Almost surely, 2^{221678048591999} is an apocalyptic number.

221678048591999 is a deficient number, since it is larger than the sum of its proper divisors (1618087946065).

221678048591999 is a wasteful number, since it uses less digits than its factorization.

221678048591999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1618087946064.

The product of its (nonzero) digits is 1410877440, while the sum is 80.

The spelling of 221678048591999 in words is "two hundred twenty-one trillion, six hundred seventy-eight billion, forty-eight million, five hundred ninety-one thousand, nine hundred ninety-nine".