12521813 has 4 divisors (see below), whose sum is σ = 12643488. Its totient is φ = 12400140.

The previous prime is 12521801. The next prime is 12521837. The reversal of 12521813 is 31812521.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12521813 - 2⁴ = 12521797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12521863) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 60683 + ... + 60888.

It is an arithmetic number, because the mean of its divisors is an integer number (3160872).

Almost surely, 2^12521813 is an apocalyptic number.

It is an amenable number.

12521813 is a deficient number, since it is larger than the sum of its proper divisors (121675).

12521813 is a wasteful number, since it uses less digits than its factorization.

12521813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121674.

The product of its digits is 480, while the sum is 23.

The square root of 12521813 is about 3538.6173853640. The cubic root of 12521813 is about 232.2143592019.

The spelling of 12521813 in words is "twelve million, five hundred twenty-one thousand, eight hundred thirteen".