16159958679721 has 2 divisors, whose sum is σ = 16159958679722. Its totient is φ = 16159958679720.

The previous prime is 16159958679707. The next prime is 16159958679763. The reversal of 16159958679721 is 12797685995161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12558086100121 + 3601872579600 = 3543739^2 + 1897860^2 .

It is a cyclic number.

It is not a de Polignac number, because 16159958679721 - 2³³ = 16151368745129 is a prime.

It is a super-2 number, since 2×16159958679721² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16159958673721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8079979339860 + 8079979339861.

It is an arithmetic number, because the mean of its divisors is an integer number (8079979339861).

Almost surely, 2^{16159958679721} is an apocalyptic number.

It is an amenable number.

16159958679721 is a deficient number, since it is larger than the sum of its proper divisors (1).

16159958679721 is an equidigital number, since it uses as much as digits as its factorization.

16159958679721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 514382400, while the sum is 76.

The spelling of 16159958679721 in words is "sixteen trillion, one hundred fifty-nine billion, nine hundred fifty-eight million, six hundred seventy-nine thousand, seven hundred twenty-one".