867999991 has 8 divisors (see below), whose sum is σ = 923680800. Its totient is φ = 812832768.

The previous prime is 867999911. The next prime is 868000033. The reversal of 867999991 is 199999768.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 867999991 - 2¹³ = 867991799 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 (867999911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124906 + ... + 131671.

It is an arithmetic number, because the mean of its divisors is an integer number (115460100).

Almost surely, 2^867999991 is an apocalyptic number.

867999991 is a deficient number, since it is larger than the sum of its proper divisors (55680809).

867999991 is a wasteful number, since it uses less digits than its factorization.

867999991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256793.

The product of its digits is 19840464, while the sum is 67.

The square root of 867999991 is about 29461.8395725725. The cubic root of 867999991 is about 953.9081812546.

The spelling of 867999991 in words is "eight hundred sixty-seven million, nine hundred ninety-nine thousand, nine hundred ninety-one".