12015421 has 12 divisors (see below), whose sum is σ = 13300000. Its totient is φ = 10846440.

The previous prime is 12015373. The next prime is 12015427. The reversal of 12015421 is 12451021.

It is not a de Polignac number, because 12015421 - 2¹⁵ = 11982653 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12015395 and 12015404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12015427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23830 + ... + 24328.

Almost surely, 2^12015421 is an apocalyptic number.

12015421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12015421 is a deficient number, since it is larger than the sum of its proper divisors (1284579).

12015421 is a wasteful number, since it uses less digits than its factorization.

12015421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720 (or 709 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 12015421 is about 3466.3267301280. The cubic root of 12015421 is about 229.0408767441.

Adding to 12015421 its reverse (12451021), we get a palindrome (24466442).

Subtracting 12015421 from its reverse (12451021), we obtain a square (435600 = 660²).

The spelling of 12015421 in words is "twelve million, fifteen thousand, four hundred twenty-one".