12125421 has 24 divisors (see below), whose sum is σ = 21837504. Its totient is φ = 6298560.

The previous prime is 12125419. The next prime is 12125423. The reversal of 12125421 is 12452121.

12125421 is a `hidden beast` number, since 121 + 2 + 542 + 1 = 666.

12125421 is digitally balanced in base 2, base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12125419) and next prime (12125423).

It is not a de Polignac number, because 12125421 - 2¹ = 12125419 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12125394 and 12125403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12125423) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8056 + ... + 9441.

It is an arithmetic number, because the mean of its divisors is an integer number (909896).

Almost surely, 2^12125421 is an apocalyptic number.

12125421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12125421 is a deficient number, since it is larger than the sum of its proper divisors (9712083).

12125421 is a wasteful number, since it uses less digits than its factorization.

12125421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17521 (or 17518 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 12125421 is about 3482.1575208482. The cubic root of 12125421 is about 229.7377035061.

Adding to 12125421 its reverse (12452121), we get a palindrome (24577542).

The spelling of 12125421 in words is "twelve million, one hundred twenty-five thousand, four hundred twenty-one".