221000879999 has 16 divisors (see below), whose sum is σ = 234106574592. Its totient is φ = 208188085248.

The previous prime is 221000879941. The next prime is 221000880011. The reversal of 221000879999 is 999978000122.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221000879999 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 (221000879399) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7679852 + ... + 7708574.

It is an arithmetic number, because the mean of its divisors is an integer number (14631660912).

Almost surely, 2^221000879999 is an apocalyptic number.

221000879999 is a deficient number, since it is larger than the sum of its proper divisors (13105694593).

221000879999 is a wasteful number, since it uses less digits than its factorization.

221000879999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33806.

The product of its (nonzero) digits is 1469664, while the sum is 56.

The spelling of 221000879999 in words is "two hundred twenty-one billion, eight hundred seventy-nine thousand, nine hundred ninety-nine".