16521275418 has 8 divisors (see below), whose sum is σ = 33042550848. Its totient is φ = 5507091804.

The previous prime is 16521275357. The next prime is 16521275471. The reversal of 16521275418 is 81457212561.

It is a happy number.

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

16521275418 is an admirable number.

It is a super-2 number, since 2×16521275418² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 16521275418.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1376772946 + ... + 1376772957.

It is an arithmetic number, because the mean of its divisors is an integer number (4130318856).

Almost surely, 2^16521275418 is an apocalyptic number.

16521275418 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16521275418 is a wasteful number, since it uses less digits than its factorization.

16521275418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2753545908.

The product of its digits is 134400, while the sum is 42.

Adding to 16521275418 its reverse (81457212561), we get a palindrome (97978487979).

The spelling of 16521275418 in words is "sixteen billion, five hundred twenty-one million, two hundred seventy-five thousand, four hundred eighteen".