16722257 has 4 divisors (see below), whose sum is σ = 16731300. Its totient is φ = 16713216.

The previous prime is 16722253. The next prime is 16722269. The reversal of 16722257 is 75222761.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 75222761 = 3187 ⋅23603.

It can be written as a sum of positive squares in 2 ways, for example, as 13845841 + 2876416 = 3721^2 + 1696^2 .

It is a cyclic number.

It is not a de Polignac number, because 16722257 - 2² = 16722253 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16722253) 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, 632 + ... + 5817.

It is an arithmetic number, because the mean of its divisors is an integer number (4182825).

Almost surely, 2^16722257 is an apocalyptic number.

It is an amenable number.

16722257 is a deficient number, since it is larger than the sum of its proper divisors (9043).

16722257 is an equidigital number, since it uses as much as digits as its factorization.

16722257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9042.

The product of its digits is 11760, while the sum is 32.

The square root of 16722257 is about 4089.2856344354. The cubic root of 16722257 is about 255.7201582782.

The spelling of 16722257 in words is "sixteen million, seven hundred twenty-two thousand, two hundred fifty-seven".