221421255546664 has 16 divisors (see below), whose sum is σ = 415167107584320. Its totient is φ = 110710026857520.

The previous prime is 221421255546649. The next prime is 221421255546679. The reversal of 221421255546664 is 466645552124122.

It is an interprime number because it is at equal distance from previous prime (221421255546649) and next prime (221421255546679).

It is a super-2 number, since 2×221421255546664² (a number of 29 digits) contains 22 as substring.

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, 73546542 + ... + 76497949.

It is an arithmetic number, because the mean of its divisors is an integer number (25947944224020).

Almost surely, 2^{221421255546664} is an apocalyptic number.

It is an amenable number.

221421255546664 is a deficient number, since it is larger than the sum of its proper divisors (193745852037656).

221421255546664 is a wasteful number, since it uses less digits than its factorization.

221421255546664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150228960 (or 150228956 counting only the distinct ones).

The product of its digits is 27648000, while the sum is 55.

The spelling of 221421255546664 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-four".