16691167278889 has 6 divisors (see below), whose sum is σ = 16823628663594. Its totient is φ = 16559740748880.

The previous prime is 16691167278857. The next prime is 16691167278931. The reversal of 16691167278889 is 98887276119661.

It can be written as a sum of positive squares in only one way, i.e., 16331838965289 + 359328313600 = 4041267^2 + 599440^2 .

It is not a de Polignac number, because 16691167278889 - 2⁵ = 16691167278857 is a prime.

It is a super-4 number, since 4×16691167278889⁴ (a number of 54 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16691167278689) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 517411092 + ... + 517443349.

It is an arithmetic number, because the mean of its divisors is an integer number (2803938110599).

Almost surely, 2^{16691167278889} is an apocalyptic number.

It is an amenable number.

16691167278889 is a deficient number, since it is larger than the sum of its proper divisors (132461384705).

16691167278889 is an equidigital number, since it uses as much as digits as its factorization.

16691167278889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1034854695 (or 1034854568 counting only the distinct ones).

The product of its digits is 877879296, while the sum is 79.

The spelling of 16691167278889 in words is "sixteen trillion, six hundred ninety-one billion, one hundred sixty-seven million, two hundred seventy-eight thousand, eight hundred eighty-nine".