87905591 has 4 divisors (see below), whose sum is σ = 89018400. Its totient is φ = 86792784.

The previous prime is 87905581. The next prime is 87905611. The reversal of 87905591 is 19550978.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 87905591 - 2⁶ = 87905527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87905501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 556286 + ... + 556443.

It is an arithmetic number, because the mean of its divisors is an integer number (22254600).

Almost surely, 2^87905591 is an apocalyptic number.

87905591 is a deficient number, since it is larger than the sum of its proper divisors (1112809).

87905591 is a wasteful number, since it uses less digits than its factorization.

87905591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112808.

The product of its (nonzero) digits is 113400, while the sum is 44.

The square root of 87905591 is about 9375.7981526908. The cubic root of 87905591 is about 444.6368977606.

The spelling of 87905591 in words is "eighty-seven million, nine hundred five thousand, five hundred ninety-one".