87291599 has 4 divisors (see below), whose sum is σ = 87377136. Its totient is φ = 87206064.

The previous prime is 87291577. The next prime is 87291641. The reversal of 87291599 is 99519278.

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 87291599 - 2¹⁶ = 87226063 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 (87291559) 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, 41219 + ... + 43284.

It is an arithmetic number, because the mean of its divisors is an integer number (21844284).

Almost surely, 2^87291599 is an apocalyptic number.

87291599 is a deficient number, since it is larger than the sum of its proper divisors (85537).

87291599 is a wasteful number, since it uses less digits than its factorization.

87291599 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85536.

The product of its digits is 408240, while the sum is 50.

The square root of 87291599 is about 9342.9973241996. The cubic root of 87291599 is about 443.5992633828.

Adding to 87291599 its sum of digits (50), we get a square (87291649 = 9343²).

The spelling of 87291599 in words is "eighty-seven million, two hundred ninety-one thousand, five hundred ninety-nine".