221231661226 has 4 divisors (see below), whose sum is σ = 331847491842. Its totient is φ = 110615830612.

The previous prime is 221231661223. The next prime is 221231661241. The reversal of 221231661226 is 622166132122.

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

It can be written as a sum of positive squares in only one way, i.e., 130284180601 + 90947480625 = 360949^2 + 301575^2 .

It is a super-3 number, since 3×221231661226³ (a number of 35 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221231661191 and 221231661200.

It is not an unprimeable number, because it can be changed into a prime (221231661223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55307915305 + ... + 55307915308.

Almost surely, 2^221231661226 is an apocalyptic number.

221231661226 is a deficient number, since it is larger than the sum of its proper divisors (110615830616).

221231661226 is a wasteful number, since it uses less digits than its factorization.

221231661226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110615830615.

The product of its digits is 20736, while the sum is 34.

Adding to 221231661226 its reverse (622166132122), we get a palindrome (843397793348).

The spelling of 221231661226 in words is "two hundred twenty-one billion, two hundred thirty-one million, six hundred sixty-one thousand, two hundred twenty-six".