866995949 has 2 divisors, whose sum is σ = 866995950. Its totient is φ = 866995948.

The previous prime is 866995939. The next prime is 866995979. The reversal of 866995949 is 949599668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 533933449 + 333062500 = 23107^2 + 18250^2 .

It is a cyclic number.

It is not a de Polignac number, because 866995949 - 2⁴ = 866995933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866995939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433497974 + 433497975.

It is an arithmetic number, because the mean of its divisors is an integer number (433497975).

Almost surely, 2^866995949 is an apocalyptic number.

It is an amenable number.

866995949 is a deficient number, since it is larger than the sum of its proper divisors (1).

866995949 is an equidigital number, since it uses as much as digits as its factorization.

866995949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37791360, while the sum is 65.

The square root of 866995949 is about 29444.7949390041. The cubic root of 866995949 is about 953.5402344739.

The spelling of 866995949 in words is "eight hundred sixty-six million, nine hundred ninety-five thousand, nine hundred forty-nine".