12521999 has 6 divisors (see below), whose sum is σ = 14566464. Its totient is φ = 10733100.

The previous prime is 12521989. The next prime is 12522011. The reversal of 12521999 is 99912521.

It is not a de Polignac number, because 12521999 - 2¹⁶ = 12456463 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 (12521989) 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 5 ways as a sum of consecutive naturals, for example, 127727 + ... + 127824.

It is an arithmetic number, because the mean of its divisors is an integer number (2427744).

Almost surely, 2^12521999 is an apocalyptic number.

12521999 is a deficient number, since it is larger than the sum of its proper divisors (2044465).

12521999 is an equidigital number, since it uses as much as digits as its factorization.

12521999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255565 (or 255558 counting only the distinct ones).

The product of its digits is 14580, while the sum is 38.

The square root of 12521999 is about 3538.6436667175. The cubic root of 12521999 is about 232.2155089730.

The spelling of 12521999 in words is "twelve million, five hundred twenty-one thousand, nine hundred ninety-nine".