65518321 has 4 divisors (see below), whose sum is σ = 71474544. Its totient is φ = 59562100.

The previous prime is 65518307. The next prime is 65518333. The reversal of 65518321 is 12381556.

It is the 3305-th star number.

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 a cyclic number.

It is not a de Polignac number, because 65518321 - 2²⁵ = 31963889 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65518351) 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, 2978095 + ... + 2978116.

It is an arithmetic number, because the mean of its divisors is an integer number (17868636).

Almost surely, 2^65518321 is an apocalyptic number.

It is an amenable number.

65518321 is a deficient number, since it is larger than the sum of its proper divisors (5956223).

65518321 is a wasteful number, since it uses less digits than its factorization.

65518321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5956222.

The product of its digits is 7200, while the sum is 31.

The square root of 65518321 is about 8094.3388241412. The cubic root of 65518321 is about 403.1384792160.

Adding to 65518321 its reverse (12381556), we get a palindrome (77899877).

The spelling of 65518321 in words is "sixty-five million, five hundred eighteen thousand, three hundred twenty-one".