12222661 has 4 divisors (see below), whose sum is σ = 13333824. Its totient is φ = 11111500.

The previous prime is 12222647. The next prime is 12222667. The reversal of 12222661 is 16622221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12222661 - 2⁵ = 12222629 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 (12222667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 555565 + ... + 555586.

It is an arithmetic number, because the mean of its divisors is an integer number (3333456).

Almost surely, 2^12222661 is an apocalyptic number.

12222661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12222661 is the 1564-th centered decagonal number.

It is an amenable number.

12222661 is a deficient number, since it is larger than the sum of its proper divisors (1111163).

12222661 is a wasteful number, since it uses less digits than its factorization.

12222661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111162.

The product of its digits is 576, while the sum is 22.

The square root of 12222661 is about 3496.0922470667. The cubic root of 12222661 is about 230.3501974584.

Adding to 12222661 its reverse (16622221), we get a palindrome (28844882).

It can be divided in two parts, 1222 and 2661, that added together give a palindrome (3883).

The spelling of 12222661 in words is "twelve million, two hundred twenty-two thousand, six hundred sixty-one".