16601616391 has 2 divisors, whose sum is σ = 16601616392. Its totient is φ = 16601616390.

The previous prime is 16601616389. The next prime is 16601616401. The reversal of 16601616391 is 19361610661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16601616391 - 2¹ = 16601616389 is a prime.

It is a super-2 number, since 2×16601616391² (a number of 21 digits) contains 22 as substring.

Together with 16601616389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16601616331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8300808195 + 8300808196.

It is an arithmetic number, because the mean of its divisors is an integer number (8300808196).

Almost surely, 2^16601616391 is an apocalyptic number.

16601616391 is a deficient number, since it is larger than the sum of its proper divisors (1).

16601616391 is an equidigital number, since it uses as much as digits as its factorization.

16601616391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 40.

The spelling of 16601616391 in words is "sixteen billion, six hundred one million, six hundred sixteen thousand, three hundred ninety-one".