16521371 has 2 divisors, whose sum is σ = 16521372. Its totient is φ = 16521370.

The previous prime is 16521367. The next prime is 16521377. The reversal of 16521371 is 17312561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16521371 - 2² = 16521367 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16521371.

It is not a weakly prime, because it can be changed into another prime (16521377) 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 as a sum of consecutive naturals, namely, 8260685 + 8260686.

It is an arithmetic number, because the mean of its divisors is an integer number (8260686).

Almost surely, 2^16521371 is an apocalyptic number.

16521371 is a deficient number, since it is larger than the sum of its proper divisors (1).

16521371 is an equidigital number, since it uses as much as digits as its factorization.

16521371 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1260, while the sum is 26.

The square root of 16521371 is about 4064.6489393304. The cubic root of 16521371 is about 254.6920337005.

The spelling of 16521371 in words is "sixteen million, five hundred twenty-one thousand, three hundred seventy-one".