8449211891 has 2 divisors, whose sum is σ = 8449211892. Its totient is φ = 8449211890.

The previous prime is 8449211887. The next prime is 8449211909. The reversal of 8449211891 is 1981129448.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 8449211891 - 2² = 8449211887 is a prime.

It is not a weakly prime, because it can be changed into another prime (8449211791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4224605945 + 4224605946.

It is an arithmetic number, because the mean of its divisors is an integer number (4224605946).

Almost surely, 2^8449211891 is an apocalyptic number.

8449211891 is a deficient number, since it is larger than the sum of its proper divisors (1).

8449211891 is an equidigital number, since it uses as much as digits as its factorization.

8449211891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165888, while the sum is 47.

The square root of 8449211891 is about 91919.5947064607. The cubic root of 8449211891 is about 2036.7547314140.

The spelling of 8449211891 in words is "eight billion, four hundred forty-nine million, two hundred eleven thousand, eight hundred ninety-one".