12154439849 has 2 divisors, whose sum is σ = 12154439850. Its totient is φ = 12154439848.

The previous prime is 12154439839. The next prime is 12154439863. The reversal of 12154439849 is 94893445121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6087120400 + 6067319449 = 78020^2 + 77893^2 .

It is an emirp because it is prime and its reverse (94893445121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12154439849 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12154439797 and 12154439806.

It is not a weakly prime, because it can be changed into another prime (12154439839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6077219924 + 6077219925.

It is an arithmetic number, because the mean of its divisors is an integer number (6077219925).

Almost surely, 2^12154439849 is an apocalyptic number.

It is an amenable number.

12154439849 is a deficient number, since it is larger than the sum of its proper divisors (1).

12154439849 is an equidigital number, since it uses as much as digits as its factorization.

12154439849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1244160, while the sum is 50.

The spelling of 12154439849 in words is "twelve billion, one hundred fifty-four million, four hundred thirty-nine thousand, eight hundred forty-nine".