16521330 has 48 divisors (see below), whose sum is σ = 46128960. Its totient is φ = 3775968.

The previous prime is 16521293. The next prime is 16521341. The reversal of 16521330 is 3312561.

16521330 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 16521297 and 16521306.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4150 + ... + 7089.

It is an arithmetic number, because the mean of its divisors is an integer number (961020).

Almost surely, 2^16521330 is an apocalyptic number.

16521330 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16521330 is an abundant number, since it is smaller than the sum of its proper divisors (29607630).

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

16521330 is a wasteful number, since it uses less digits than its factorization.

16521330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11263 (or 11256 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 16521330 is about 4064.6438958413. The cubic root of 16521330 is about 254.6918230162.

Adding to 16521330 its reverse (3312561), we get a palindrome (19833891).

The spelling of 16521330 in words is "sixteen million, five hundred twenty-one thousand, three hundred thirty".