22312181666 has 4 divisors (see below), whose sum is σ = 33468272502. Its totient is φ = 11156090832.

The previous prime is 22312181663. The next prime is 22312181677. The reversal of 22312181666 is 66618121322.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66618121322 = 2 ⋅33309060661.

It can be written as a sum of positive squares in only one way, i.e., 15370792441 + 6941389225 = 123979^2 + 83315^2 .

It is a super-3 number, since 3×22312181666³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (22312181663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5578045415 + ... + 5578045418.

Almost surely, 2^22312181666 is an apocalyptic number.

22312181666 is a deficient number, since it is larger than the sum of its proper divisors (11156090836).

22312181666 is a wasteful number, since it uses less digits than its factorization.

22312181666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11156090835.

The product of its digits is 41472, while the sum is 38.

The spelling of 22312181666 in words is "twenty-two billion, three hundred twelve million, one hundred eighty-one thousand, six hundred sixty-six".