947877851 has 2 divisors, whose sum is σ = 947877852. Its totient is φ = 947877850.

The previous prime is 947877781. The next prime is 947877881. The reversal of 947877851 is 158778749.

It is a strong prime.

It is an emirp because it is prime and its reverse (158778749) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-947877851 is a prime.

It is not a weakly prime, because it can be changed into another prime (947877881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 473938925 + 473938926.

It is an arithmetic number, because the mean of its divisors is an integer number (473938926).

Almost surely, 2^947877851 is an apocalyptic number.

947877851 is a deficient number, since it is larger than the sum of its proper divisors (1).

947877851 is an equidigital number, since it uses as much as digits as its factorization.

947877851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3951360, while the sum is 56.

The square root of 947877851 is about 30787.6249652356. The cubic root of 947877851 is about 982.3150360891.

The spelling of 947877851 in words is "nine hundred forty-seven million, eight hundred seventy-seven thousand, eight hundred fifty-one".