16897221 has 16 divisors (see below), whose sum is σ = 27309120. Its totient is φ = 10240560.

The previous prime is 16897211. The next prime is 16897241. The reversal of 16897221 is 12279861.

It is not a de Polignac number, because 16897221 - 2⁵ = 16897189 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16897211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28150 + ... + 28743.

It is an arithmetic number, because the mean of its divisors is an integer number (1706820).

Almost surely, 2^16897221 is an apocalyptic number.

16897221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16897221 is a deficient number, since it is larger than the sum of its proper divisors (10411899).

16897221 is a wasteful number, since it uses less digits than its factorization.

16897221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56913 (or 56907 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 16897221 is about 4110.6229454914. The cubic root of 16897221 is about 256.6089274367.

The spelling of 16897221 in words is "sixteen million, eight hundred ninety-seven thousand, two hundred twenty-one".