87918321 has 4 divisors (see below), whose sum is σ = 117224432. Its totient is φ = 58612212.

The previous prime is 87918307. The next prime is 87918329. The reversal of 87918321 is 12381978.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 87918321 - 2⁵ = 87918289 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 87918321.

It is not an unprimeable number, because it can be changed into a prime (87918329) 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, 14653051 + ... + 14653056.

It is an arithmetic number, because the mean of its divisors is an integer number (29306108).

Almost surely, 2^87918321 is an apocalyptic number.

It is an amenable number.

87918321 is a deficient number, since it is larger than the sum of its proper divisors (29306111).

87918321 is a wasteful number, since it uses less digits than its factorization.

87918321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29306110.

The product of its digits is 24192, while the sum is 39.

The square root of 87918321 is about 9376.4770036512. The cubic root of 87918321 is about 444.6583600076.

The spelling of 87918321 in words is "eighty-seven million, nine hundred eighteen thousand, three hundred twenty-one".