16657939 has 2 divisors, whose sum is σ = 16657940. Its totient is φ = 16657938.

The previous prime is 16657903. The next prime is 16657951. The reversal of 16657939 is 93975661.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16657939 is a prime.

It is not a weakly prime, because it can be changed into another prime (16657999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8328969 + 8328970.

It is an arithmetic number, because the mean of its divisors is an integer number (8328970).

Almost surely, 2^16657939 is an apocalyptic number.

16657939 is a deficient number, since it is larger than the sum of its proper divisors (1).

16657939 is an equidigital number, since it uses as much as digits as its factorization.

16657939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 306180, while the sum is 46.

The square root of 16657939 is about 4081.4138481659. The cubic root of 16657939 is about 255.3918823908.

It can be divided in two parts, 1665 and 7939, that added together give a square (9604 = 98²).

The spelling of 16657939 in words is "sixteen million, six hundred fifty-seven thousand, nine hundred thirty-nine".