216721670126 has 16 divisors (see below), whose sum is σ = 351207359664. Its totient is φ = 99705812544.

The previous prime is 216721670093. The next prime is 216721670159. The reversal of 216721670126 is 621076127612.

It is an interprime number because it is at equal distance from previous prime (216721670093) and next prime (216721670159).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13307276 + ... + 13323551.

It is an arithmetic number, because the mean of its divisors is an integer number (21950459979).

Almost surely, 2^216721670126 is an apocalyptic number.

216721670126 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

216721670126 is a deficient number, since it is larger than the sum of its proper divisors (134485689538).

216721670126 is a wasteful number, since it uses less digits than its factorization.

216721670126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26631155.

The product of its (nonzero) digits is 84672, while the sum is 41.

Adding to 216721670126 its reverse (621076127612), we get a palindrome (837797797738).

The spelling of 216721670126 in words is "two hundred sixteen billion, seven hundred twenty-one million, six hundred seventy thousand, one hundred twenty-six".