16639253207557 has 2 divisors, whose sum is σ = 16639253207558. Its totient is φ = 16639253207556.

The previous prime is 16639253207527. The next prime is 16639253207581. The reversal of 16639253207557 is 75570235293661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8606484209761 + 8032768997796 = 2933681^2 + 2834214^2 .

It is an emirp because it is prime and its reverse (75570235293661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16639253207557 - 2³⁵ = 16604893469189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16639253207495 and 16639253207504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16639253207527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8319626603778 + 8319626603779.

It is an arithmetic number, because the mean of its divisors is an integer number (8319626603779).

Almost surely, 2^{16639253207557} is an apocalyptic number.

It is an amenable number.

16639253207557 is a deficient number, since it is larger than the sum of its proper divisors (1).

16639253207557 is an equidigital number, since it uses as much as digits as its factorization.

16639253207557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 71442000, while the sum is 61.

The spelling of 16639253207557 in words is "sixteen trillion, six hundred thirty-nine billion, two hundred fifty-three million, two hundred seven thousand, five hundred fifty-seven".