842071991 has 6 divisors (see below), whose sum is σ = 844254576. Its totient is φ = 839895000.

The previous prime is 842071973. The next prime is 842072017. The reversal of 842071991 is 199170248.

It is not a de Polignac number, because 842071991 - 2¹⁸ = 841809847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842071961) 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 in 5 ways as a sum of consecutive naturals, for example, 174866 + ... + 179616.

It is an arithmetic number, because the mean of its divisors is an integer number (140709096).

Almost surely, 2^842071991 is an apocalyptic number.

842071991 is a deficient number, since it is larger than the sum of its proper divisors (2182585).

842071991 is an frugal number, since it uses more digits than its factorization.

842071991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5593 (or 5172 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 41.

The square root of 842071991 is about 29018.4767174295. The cubic root of 842071991 is about 944.3139542586.

The spelling of 842071991 in words is "eight hundred forty-two million, seventy-one thousand, nine hundred ninety-one".