12521851 has 4 divisors (see below), whose sum is σ = 12827304. Its totient is φ = 12216400.

The previous prime is 12521837. The next prime is 12521857. The reversal of 12521851 is 15812521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15812521 = 109 ⋅145069.

It is a cyclic number.

It is not a de Polignac number, because 12521851 - 2⁹ = 12521339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12521857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152665 + ... + 152746.

It is an arithmetic number, because the mean of its divisors is an integer number (3206826).

Almost surely, 2^12521851 is an apocalyptic number.

12521851 is a deficient number, since it is larger than the sum of its proper divisors (305453).

12521851 is an equidigital number, since it uses as much as digits as its factorization.

12521851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305452.

The product of its digits is 800, while the sum is 25.

The square root of 12521851 is about 3538.6227546886. The cubic root of 12521851 is about 232.2145941023.

The spelling of 12521851 in words is "twelve million, five hundred twenty-one thousand, eight hundred fifty-one".