16821105 has 16 divisors (see below), whose sum is σ = 30758784. Its totient is φ = 7689600.

The previous prime is 16821083. The next prime is 16821121. The reversal of 16821105 is 50112861.

It is not a de Polignac number, because 16821105 - 2⁸ = 16820849 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79996 + ... + 80205.

It is an arithmetic number, because the mean of its divisors is an integer number (1922424).

Almost surely, 2^16821105 is an apocalyptic number.

16821105 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16821105 is a deficient number, since it is larger than the sum of its proper divisors (13937679).

16821105 is a wasteful number, since it uses less digits than its factorization.

16821105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160216.

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 16821105 is about 4101.3540447028. The cubic root of 16821105 is about 256.2230366236.

Adding to 16821105 its reverse (50112861), we get a palindrome (66933966).

It can be divided in two parts, 16 and 821105, that added together give a triangular number (821121 = T₁₂₈₁).

The spelling of 16821105 in words is "sixteen million, eight hundred twenty-one thousand, one hundred five".