87289681 has 8 divisors (see below), whose sum is σ = 90616680. Its totient is φ = 83983872.

The previous prime is 87289673. The next prime is 87289703. The reversal of 87289681 is 18698278.

It can be written as a sum of positive squares in 4 ways, for example, as 22648081 + 64641600 = 4759^2 + 8040^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 87289681 - 2³ = 87289673 is a prime.

It is a super-4 number, since 4×87289681⁴ (a number of 33 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87289651) 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, 3361 + ... + 13633.

It is an arithmetic number, because the mean of its divisors is an integer number (11327085).

Almost surely, 2^87289681 is an apocalyptic number.

It is an amenable number.

87289681 is a deficient number, since it is larger than the sum of its proper divisors (3326999).

87289681 is a wasteful number, since it uses less digits than its factorization.

87289681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10595.

The product of its digits is 387072, while the sum is 49.

The square root of 87289681 is about 9342.8946799159. The cubic root of 87289681 is about 443.5960143889.

The spelling of 87289681 in words is "eighty-seven million, two hundred eighty-nine thousand, six hundred eighty-one".