12215406 has 24 divisors (see below), whose sum is σ = 28420200. Its totient is φ = 3490032.

The previous prime is 12215393. The next prime is 12215429. The reversal of 12215406 is 60451221.

It is a super-2 number, since 2×12215406² = 298432287489672, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20481 + ... + 21068.

It is an arithmetic number, because the mean of its divisors is an integer number (1184175).

Almost surely, 2^12215406 is an apocalyptic number.

12215406 is an abundant number, since it is smaller than the sum of its proper divisors (16204794).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12215406 is a wasteful number, since it uses less digits than its factorization.

12215406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41568 (or 41561 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 12215406 is about 3495.0545060127. The cubic root of 12215406 is about 230.3046121464.

Adding to 12215406 its reverse (60451221), we get a palindrome (72666627).

It can be divided in two parts, 12215 and 406, that added together give a palindrome (12621).

The spelling of 12215406 in words is "twelve million, two hundred fifteen thousand, four hundred six".