221421255546667 has 4 divisors (see below), whose sum is σ = 241550460596376. Its totient is φ = 201292050496960.

The previous prime is 221421255546649. The next prime is 221421255546679. The reversal of 221421255546667 is 766645552124122.

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

It is a cyclic number.

It is not a de Polignac number, because 221421255546667 - 2⁷ = 221421255546539 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221421255516667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10064602524838 + ... + 10064602524859.

It is an arithmetic number, because the mean of its divisors is an integer number (60387615149094).

Almost surely, 2^{221421255546667} is an apocalyptic number.

221421255546667 is a deficient number, since it is larger than the sum of its proper divisors (20129205049709).

221421255546667 is a wasteful number, since it uses less digits than its factorization.

221421255546667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20129205049708.

The product of its digits is 48384000, while the sum is 58.

The spelling of 221421255546667 in words is "two hundred twenty-one trillion, four hundred twenty-one billion, two hundred fifty-five million, five hundred forty-six thousand, six hundred sixty-seven".