16221237 has 8 divisors (see below), whose sum is σ = 22374240. Its totient is φ = 10441200.

The previous prime is 16221223. The next prime is 16221239. The reversal of 16221237 is 73212261.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16221237 - 2⁷ = 16221109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 93139 + ... + 93312.

It is an arithmetic number, because the mean of its divisors is an integer number (2796780).

Almost surely, 2^16221237 is an apocalyptic number.

It is an amenable number.

16221237 is a deficient number, since it is larger than the sum of its proper divisors (6153003).

16221237 is a wasteful number, since it uses less digits than its factorization.

16221237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186483.

The product of its digits is 1008, while the sum is 24.

The square root of 16221237 is about 4027.5596829842. The cubic root of 16221237 is about 253.1403190851.

Adding to 16221237 its reverse (73212261), we get a palindrome (89433498).

The spelling of 16221237 in words is "sixteen million, two hundred twenty-one thousand, two hundred thirty-seven".