16505971 has 2 divisors, whose sum is σ = 16505972. Its totient is φ = 16505970.

The previous prime is 16505969. The next prime is 16505987. The reversal of 16505971 is 17950561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16505971 - 2¹ = 16505969 is a prime.

Together with 16505969, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16505911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8252985 + 8252986.

It is an arithmetic number, because the mean of its divisors is an integer number (8252986).

Almost surely, 2^16505971 is an apocalyptic number.

16505971 is a deficient number, since it is larger than the sum of its proper divisors (1).

16505971 is an equidigital number, since it uses as much as digits as its factorization.

16505971 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9450, while the sum is 34.

The square root of 16505971 is about 4062.7541151293. The cubic root of 16505971 is about 254.6128740749.

The spelling of 16505971 in words is "sixteen million, five hundred five thousand, nine hundred seventy-one".