12212421 has 16 divisors (see below), whose sum is σ = 18459840. Its totient is φ = 7119360.

The previous prime is 12212413. The next prime is 12212423. The reversal of 12212421 is 12421221.

12212421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12212421 - 2³ = 12212413 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12212421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12212423) 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, 7500 + ... + 8981.

It is an arithmetic number, because the mean of its divisors is an integer number (1153740).

Almost surely, 2^12212421 is an apocalyptic number.

It is an amenable number.

12212421 is a deficient number, since it is larger than the sum of its proper divisors (6247419).

12212421 is a wasteful number, since it uses less digits than its factorization.

12212421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16516.

The product of its digits is 64, while the sum is 15.

The square root of 12212421 is about 3494.6274479549. The cubic root of 12212421 is about 230.2858512671.

Adding to 12212421 its reverse (12421221), we get a palindrome (24633642).

The spelling of 12212421 in words is "twelve million, two hundred twelve thousand, four hundred twenty-one".