12215851 has 2 divisors, whose sum is σ = 12215852. Its totient is φ = 12215850.

The previous prime is 12215831. The next prime is 12215897. The reversal of 12215851 is 15851221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12215851 - 2²¹ = 10118699 is a prime.

It is not a weakly prime, because it can be changed into another prime (12215821) 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 as a sum of consecutive naturals, namely, 6107925 + 6107926.

It is an arithmetic number, because the mean of its divisors is an integer number (6107926).

Almost surely, 2^12215851 is an apocalyptic number.

12215851 is a deficient number, since it is larger than the sum of its proper divisors (1).

12215851 is an equidigital number, since it uses as much as digits as its factorization.

12215851 is an odious number, because the sum of its binary digits is odd.

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

The square root of 12215851 is about 3495.1181668150. The cubic root of 12215851 is about 230.3074087326.

The spelling of 12215851 in words is "twelve million, two hundred fifteen thousand, eight hundred fifty-one".