87109989 has 8 divisors (see below), whose sum is σ = 122978880. Its totient is φ = 54657216.

The previous prime is 87109973. The next prime is 87109991. The reversal of 87109989 is 98990178.

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

It is not a de Polignac number, because 87109989 - 2⁴ = 87109973 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51), and also a Moran number because the ratio is a prime number: 1708039 = 87109989 / (8 + 7 + 1 + 0 + 9 + 9 + 8 + 9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87109949) 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, 853969 + ... + 854070.

It is an arithmetic number, because the mean of its divisors is an integer number (15372360).

Almost surely, 2^87109989 is an apocalyptic number.

It is an amenable number.

87109989 is a deficient number, since it is larger than the sum of its proper divisors (35868891).

87109989 is a wasteful number, since it uses less digits than its factorization.

87109989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1708059.

The product of its (nonzero) digits is 326592, while the sum is 51.

The square root of 87109989 is about 9333.2732200445. The cubic root of 87109989 is about 443.2914139924.

The spelling of 87109989 in words is "eighty-seven million, one hundred nine thousand, nine hundred eighty-nine".