87791181 has 8 divisors (see below), whose sum is σ = 117365280. Its totient is φ = 58372272.

The previous prime is 87791177. The next prime is 87791189. The reversal of 87791181 is 18119778.

It is a happy number.

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

It is not a de Polignac number, because 87791181 - 2² = 87791177 is a prime.

It is a super-2 number, since 2×87791181² = 15414582922749522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87791189) 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, 37470 + ... + 39743.

It is an arithmetic number, because the mean of its divisors is an integer number (14670660).

Almost surely, 2^87791181 is an apocalyptic number.

It is an amenable number.

87791181 is a deficient number, since it is larger than the sum of its proper divisors (29574099).

87791181 is a wasteful number, since it uses less digits than its factorization.

87791181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77595.

The product of its digits is 28224, while the sum is 42.

The square root of 87791181 is about 9369.6948189362. The cubic root of 87791181 is about 444.4439142332.

The spelling of 87791181 in words is "eighty-seven million, seven hundred ninety-one thousand, one hundred eighty-one".