16321537 has 2 divisors, whose sum is σ = 16321538. Its totient is φ = 16321536.

The previous prime is 16321507. The next prime is 16321541. The reversal of 16321537 is 73512361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11999296 + 4322241 = 3464^2 + 2079^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16321537 is a prime.

It is not a weakly prime, because it can be changed into another prime (16321507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8160768 + 8160769.

It is an arithmetic number, because the mean of its divisors is an integer number (8160769).

Almost surely, 2^16321537 is an apocalyptic number.

It is an amenable number.

16321537 is a deficient number, since it is larger than the sum of its proper divisors (1).

16321537 is an equidigital number, since it uses as much as digits as its factorization.

16321537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 28.

The square root of 16321537 is about 4039.9922029628. The cubic root of 16321537 is about 253.6609908883.

Adding to 16321537 its reverse (73512361), we get a palindrome (89833898).

The spelling of 16321537 in words is "sixteen million, three hundred twenty-one thousand, five hundred thirty-seven".