87805581 has 8 divisors (see below), whose sum is σ = 117600000. Its totient is φ = 58274112.

The previous prime is 87805579. The next prime is 87805589. The reversal of 87805581 is 18550878.

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

It is not a de Polignac number, because 87805581 - 2¹ = 87805579 is a prime.

It is a super-2 number, since 2×87805581² = 15419640109495122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87805589) 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, 64956 + ... + 66293.

It is an arithmetic number, because the mean of its divisors is an integer number (14700000).

Almost surely, 2^87805581 is an apocalyptic number.

It is an amenable number.

87805581 is a deficient number, since it is larger than the sum of its proper divisors (29794419).

87805581 is a wasteful number, since it uses less digits than its factorization.

87805581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131475.

The product of its (nonzero) digits is 89600, while the sum is 42.

The square root of 87805581 is about 9370.4632222746. The cubic root of 87805581 is about 444.4682129627.

The spelling of 87805581 in words is "eighty-seven million, eight hundred five thousand, five hundred eighty-one".