16639289 has 2 divisors, whose sum is σ = 16639290. Its totient is φ = 16639288.

The previous prime is 16639279. The next prime is 16639333. The reversal of 16639289 is 98293661.

It is an a-pointer prime, because the next prime (16639333) can be obtained adding 16639289 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14440000 + 2199289 = 3800^2 + 1483^2 .

It is a cyclic number.

It is not a de Polignac number, because 16639289 - 2¹² = 16635193 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16639279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8319644 + 8319645.

It is an arithmetic number, because the mean of its divisors is an integer number (8319645).

Almost surely, 2^16639289 is an apocalyptic number.

It is an amenable number.

16639289 is a deficient number, since it is larger than the sum of its proper divisors (1).

16639289 is an equidigital number, since it uses as much as digits as its factorization.

16639289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 44.

The square root of 16639289 is about 4079.1284608357. The cubic root of 16639289 is about 255.2965357163.

The spelling of 16639289 in words is "sixteen million, six hundred thirty-nine thousand, two hundred eighty-nine".