16649957 has 2 divisors, whose sum is σ = 16649958. Its totient is φ = 16649956.

The previous prime is 16649933. The next prime is 16649959. The reversal of 16649957 is 75994661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16370116 + 279841 = 4046^2 + 529^2 .

It is a cyclic number.

It is not a de Polignac number, because 16649957 - 2²⁰ = 15601381 is a prime.

Together with 16649959, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16649959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8324978 + 8324979.

It is an arithmetic number, because the mean of its divisors is an integer number (8324979).

Almost surely, 2^16649957 is an apocalyptic number.

It is an amenable number.

16649957 is a deficient number, since it is larger than the sum of its proper divisors (1).

16649957 is an equidigital number, since it uses as much as digits as its factorization.

16649957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 408240, while the sum is 47.

The square root of 16649957 is about 4080.4358835791. The cubic root of 16649957 is about 255.3510837523.

The spelling of 16649957 in words is "sixteen million, six hundred forty-nine thousand, nine hundred fifty-seven".