12151861 has 2 divisors, whose sum is σ = 12151862. Its totient is φ = 12151860.

The previous prime is 12151847. The next prime is 12151891. The reversal of 12151861 is 16815121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11088900 + 1062961 = 3330^2 + 1031^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12151861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12151801) 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, 6075930 + 6075931.

It is an arithmetic number, because the mean of its divisors is an integer number (6075931).

Almost surely, 2^12151861 is an apocalyptic number.

It is an amenable number.

12151861 is a deficient number, since it is larger than the sum of its proper divisors (1).

12151861 is an equidigital number, since it uses as much as digits as its factorization.

12151861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 480, while the sum is 25.

The square root of 12151861 is about 3485.9519503286. The cubic root of 12151861 is about 229.9045665827.

Adding to 12151861 its reverse (16815121), we get a palindrome (28966982).

The spelling of 12151861 in words is "twelve million, one hundred fifty-one thousand, eight hundred sixty-one".