16227821 has 2 divisors, whose sum is σ = 16227822. Its totient is φ = 16227820.

The previous prime is 16227803. The next prime is 16227839. The reversal of 16227821 is 12872261.

It is a balanced prime because it is at equal distance from previous prime (16227803) and next prime (16227839).

It can be written as a sum of positive squares in only one way, i.e., 13468900 + 2758921 = 3670^2 + 1661^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16227821 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16227851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8113910 + 8113911.

It is an arithmetic number, because the mean of its divisors is an integer number (8113911).

Almost surely, 2^16227821 is an apocalyptic number.

It is an amenable number.

16227821 is a deficient number, since it is larger than the sum of its proper divisors (1).

16227821 is an equidigital number, since it uses as much as digits as its factorization.

16227821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2688, while the sum is 29.

The square root of 16227821 is about 4028.3769684576. The cubic root of 16227821 is about 253.1745632967.

The spelling of 16227821 in words is "sixteen million, two hundred twenty-seven thousand, eight hundred twenty-one".