818621849 has 2 divisors, whose sum is σ = 818621850. Its totient is φ = 818621848.

The previous prime is 818621803. The next prime is 818621857. The reversal of 818621849 is 948126818.

It is a happy number.

818621849 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 797045824 + 21576025 = 28232^2 + 4645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-818621849 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (818621899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409310924 + 409310925.

It is an arithmetic number, because the mean of its divisors is an integer number (409310925).

Almost surely, 2^818621849 is an apocalyptic number.

It is an amenable number.

818621849 is a deficient number, since it is larger than the sum of its proper divisors (1).

818621849 is an equidigital number, since it uses as much as digits as its factorization.

818621849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 221184, while the sum is 47.

The square root of 818621849 is about 28611.5684470460. The cubic root of 818621849 is about 935.4655041407.

The spelling of 818621849 in words is "eight hundred eighteen million, six hundred twenty-one thousand, eight hundred forty-nine".