88665991 has 4 divisors (see below), whose sum is σ = 89989432. Its totient is φ = 87342552.

The previous prime is 88665977. The next prime is 88666003. The reversal of 88665991 is 19956688.

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 88665991 - 2¹¹ = 88663943 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 (88665911) 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, 661620 + ... + 661753.

It is an arithmetic number, because the mean of its divisors is an integer number (22497358).

Almost surely, 2^88665991 is an apocalyptic number.

88665991 is a deficient number, since it is larger than the sum of its proper divisors (1323441).

88665991 is a wasteful number, since it uses less digits than its factorization.

88665991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1323440.

The product of its digits is 933120, while the sum is 52.

The square root of 88665991 is about 9416.2620503043. The cubic root of 88665991 is about 445.9152831645.

The spelling of 88665991 in words is "eighty-eight million, six hundred sixty-five thousand, nine hundred ninety-one".