12421645 has 16 divisors (see below), whose sum is σ = 15866928. Its totient is φ = 9303040.

The previous prime is 12421639. The next prime is 12421681. The reversal of 12421645 is 54612421.

It is a happy number.

12421645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 1004004 + 11417641 = 1002^2 + 3379^2 .

It is not a de Polignac number, because 12421645 - 2³ = 12421637 is a prime.

It is a super-3 number, since 3×12421645³ (a number of 22 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26715 + ... + 27175.

It is an arithmetic number, because the mean of its divisors is an integer number (991683).

Almost surely, 2^12421645 is an apocalyptic number.

It is an amenable number.

12421645 is a deficient number, since it is larger than the sum of its proper divisors (3445283).

12421645 is a wasteful number, since it uses less digits than its factorization.

12421645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800.

The product of its digits is 1920, while the sum is 25.

The square root of 12421645 is about 3524.4354157794. The cubic root of 12421645 is about 231.5935026510.

The spelling of 12421645 in words is "twelve million, four hundred twenty-one thousand, six hundred forty-five".