88991309 has 4 divisors (see below), whose sum is σ = 97081440. Its totient is φ = 80901180.

The previous prime is 88991291. The next prime is 88991363. The reversal of 88991309 is 90319988.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 88991309 - 2¹⁶ = 88925773 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 (88991509) 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, 4045049 + ... + 4045070.

It is an arithmetic number, because the mean of its divisors is an integer number (24270360).

Almost surely, 2^88991309 is an apocalyptic number.

It is an amenable number.

88991309 is a deficient number, since it is larger than the sum of its proper divisors (8090131).

88991309 is a wasteful number, since it uses less digits than its factorization.

88991309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8090130.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 88991309 is about 9433.5204987322. The cubic root of 88991309 is about 446.4599760893.

The spelling of 88991309 in words is "eighty-eight million, nine hundred ninety-one thousand, three hundred nine".