86842991 has 4 divisors (see below), whose sum is σ = 88481592. Its totient is φ = 85204392.

The previous prime is 86842967. The next prime is 86842999. The reversal of 86842991 is 19924868.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 86842991 - 2⁶ = 86842927 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86842999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 819221 + ... + 819326.

It is an arithmetic number, because the mean of its divisors is an integer number (22120398).

Almost surely, 2^86842991 is an apocalyptic number.

86842991 is a deficient number, since it is larger than the sum of its proper divisors (1638601).

86842991 is a wasteful number, since it uses less digits than its factorization.

86842991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1638600.

The product of its digits is 248832, while the sum is 47.

The square root of 86842991 is about 9318.9586864628. The cubic root of 86842991 is about 442.8380444318.

The spelling of 86842991 in words is "eighty-six million, eight hundred forty-two thousand, nine hundred ninety-one".