811247849 has 2 divisors, whose sum is σ = 811247850. Its totient is φ = 811247848.

The previous prime is 811247821. The next prime is 811247851. The reversal of 811247849 is 948742118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 773952400 + 37295449 = 27820^2 + 6107^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-811247849 is a prime.

Together with 811247851, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (811247149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405623924 + 405623925.

It is an arithmetic number, because the mean of its divisors is an integer number (405623925).

Almost surely, 2^811247849 is an apocalyptic number.

It is an amenable number.

811247849 is a deficient number, since it is larger than the sum of its proper divisors (1).

811247849 is an equidigital number, since it uses as much as digits as its factorization.

811247849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129024, while the sum is 44.

The square root of 811247849 is about 28482.4129771338. The cubic root of 811247849 is about 932.6481922287.

The spelling of 811247849 in words is "eight hundred eleven million, two hundred forty-seven thousand, eight hundred forty-nine".