12221615 has 16 divisors (see below), whose sum is σ = 17340480. Its totient is φ = 8090880.

The previous prime is 12221611. The next prime is 12221669. The reversal of 12221615 is 51612221.

It is not a de Polignac number, because 12221615 - 2² = 12221611 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5006 + ... + 7035.

It is an arithmetic number, because the mean of its divisors is an integer number (1083780).

Almost surely, 2^12221615 is an apocalyptic number.

12221615 is a deficient number, since it is larger than the sum of its proper divisors (5118865).

12221615 is a wasteful number, since it uses less digits than its factorization.

12221615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12082.

The product of its digits is 240, while the sum is 20.

The square root of 12221615 is about 3495.9426482710. The cubic root of 12221615 is about 230.3436262440.

Adding to 12221615 its reverse (51612221), we get a palindrome (63833836).

The spelling of 12221615 in words is "twelve million, two hundred twenty-one thousand, six hundred fifteen".