87915581 has 8 divisors (see below), whose sum is σ = 95176704. Its totient is φ = 80725680.

The previous prime is 87915571. The next prime is 87915593. The reversal of 87915581 is 18551978.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87915581 is a prime.

It is a super-2 number, since 2×87915581² = 15458298765135122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87915571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15221 + ... + 20186.

It is an arithmetic number, because the mean of its divisors is an integer number (11897088).

Almost surely, 2^87915581 is an apocalyptic number.

It is an amenable number.

87915581 is a deficient number, since it is larger than the sum of its proper divisors (7261123).

87915581 is a wasteful number, since it uses less digits than its factorization.

87915581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35611.

The product of its digits is 100800, while the sum is 44.

The square root of 87915581 is about 9376.3308921987. The cubic root of 87915581 is about 444.6537406573.

The spelling of 87915581 in words is "eighty-seven million, nine hundred fifteen thousand, five hundred eighty-one".