68634662721 has 16 divisors (see below), whose sum is σ = 94826434560. Its totient is φ = 44126606160.

The previous prime is 68634662659. The next prime is 68634662741. The reversal of 68634662721 is 12726643686.

It is a happy number.

It is not a de Polignac number, because 68634662721 - 2⁹ = 68634662209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (68634662741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3357225 + ... + 3377606.

It is an arithmetic number, because the mean of its divisors is an integer number (5926652160).

Almost surely, 2^68634662721 is an apocalyptic number.

It is an amenable number.

68634662721 is a deficient number, since it is larger than the sum of its proper divisors (26191771839).

68634662721 is a wasteful number, since it uses less digits than its factorization.

68634662721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6734956.

The product of its digits is 3483648, while the sum is 51.

The spelling of 68634662721 in words is "sixty-eight billion, six hundred thirty-four million, six hundred sixty-two thousand, seven hundred twenty-one".