12155222 has 4 divisors (see below), whose sum is σ = 18232836. Its totient is φ = 6077610.

The previous prime is 12155191. The next prime is 12155237. The reversal of 12155222 is 22255121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 22255121 = 7 ⋅3179303.

It is a junction number, because it is equal to n+sod(n) for n = 12155194 and 12155203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3038804 + ... + 3038807.

It is an arithmetic number, because the mean of its divisors is an integer number (4558209).

Almost surely, 2^12155222 is an apocalyptic number.

12155222 is a deficient number, since it is larger than the sum of its proper divisors (6077614).

12155222 is an equidigital number, since it uses as much as digits as its factorization.

12155222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6077613.

The product of its digits is 400, while the sum is 20.

The square root of 12155222 is about 3486.4339947861. The cubic root of 12155222 is about 229.9257605386.

The spelling of 12155222 in words is "twelve million, one hundred fifty-five thousand, two hundred twenty-two".