947820851 has 2 divisors, whose sum is σ = 947820852. Its totient is φ = 947820850.

The previous prime is 947820787. The next prime is 947820919. The reversal of 947820851 is 158028749.

It is a weak prime.

It is an emirp because it is prime and its reverse (158028749) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 947820851 - 2⁶ = 947820787 is a prime.

It is not a weakly prime, because it can be changed into another prime (947820151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 473910425 + 473910426.

It is an arithmetic number, because the mean of its divisors is an integer number (473910426).

Almost surely, 2^947820851 is an apocalyptic number.

947820851 is a deficient number, since it is larger than the sum of its proper divisors (1).

947820851 is an equidigital number, since it uses as much as digits as its factorization.

947820851 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 161280, while the sum is 44.

The square root of 947820851 is about 30786.6992547106. The cubic root of 947820851 is about 982.2953454088.

The spelling of 947820851 in words is "nine hundred forty-seven million, eight hundred twenty thousand, eight hundred fifty-one".