991862847 has 8 divisors (see below), whose sum is σ = 1469426480. Its totient is φ = 661241880.

The previous prime is 991862827. The next prime is 991862849. The reversal of 991862847 is 748268199.

991862847 is a `hidden beast` number, since 9 + 9 + 1 + 8 + 628 + 4 + 7 = 666.

It is not a de Polignac number, because 991862847 - 2⁸ = 991862591 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 991862793 and 991862802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991862849) 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 in 7 ways as a sum of consecutive naturals, for example, 18367804 + ... + 18367857.

It is an arithmetic number, because the mean of its divisors is an integer number (183678310).

Almost surely, 2^991862847 is an apocalyptic number.

991862847 is a deficient number, since it is larger than the sum of its proper divisors (477563633).

991862847 is a wasteful number, since it uses less digits than its factorization.

991862847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36735670 (or 36735664 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The square root of 991862847 is about 31493.8541147317. The cubic root of 991862847 is about 997.2802251979.

The spelling of 991862847 in words is "nine hundred ninety-one million, eight hundred sixty-two thousand, eight hundred forty-seven".