88991 has 4 divisors (see below), whose sum is σ = 101712. Its totient is φ = 76272.

The previous prime is 88969. The next prime is 88993. The reversal of 88991 is 19988.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-88991 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 (88993) 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, 6350 + ... + 6363.

It is an arithmetic number, because the mean of its divisors is an integer number (25428).

2⁸⁸⁹⁹¹ is an apocalyptic number.

88991 is a deficient number, since it is larger than the sum of its proper divisors (12721).

88991 is a wasteful number, since it uses less digits than its factorization.

88991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12720.

The product of its digits is 5184, while the sum is 35.

The square root of 88991 is about 298.3135933879. The cubic root of 88991 is about 44.6459459349.

The spelling of 88991 in words is "eighty-eight thousand, nine hundred ninety-one".