68909738981 has 12 divisors (see below), whose sum is σ = 70681340196. Its totient is φ = 67181537280.

The previous prime is 68909738959. The next prime is 68909738993. The reversal of 68909738981 is 18983790986.

It can be written as a sum of positive squares in 6 ways, for example, as 24534209956 + 44375529025 = 156634^2 + 210655^2 .

It is not a de Polignac number, because 68909738981 - 2¹⁰ = 68909737957 is a prime.

It is a super-2 number, since 2×68909738981² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68909738081) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2496005 + ... + 2523461.

It is an arithmetic number, because the mean of its divisors is an integer number (5890111683).

Almost surely, 2^68909738981 is an apocalyptic number.

It is an amenable number.

68909738981 is a deficient number, since it is larger than the sum of its proper divisors (1771601215).

68909738981 is a wasteful number, since it uses less digits than its factorization.

68909738981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29032 (or 28991 counting only the distinct ones).

The product of its (nonzero) digits is 47029248, while the sum is 68.

The spelling of 68909738981 in words is "sixty-eight billion, nine hundred nine million, seven hundred thirty-eight thousand, nine hundred eighty-one".