81968635348 has 24 divisors (see below), whose sum is σ = 143733381120. Its totient is φ = 40902040800.

The previous prime is 81968635339. The next prime is 81968635349. The reversal of 81968635348 is 84353686918.

It is a super-2 number, since 2×81968635348² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81968635349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4221390 + ... + 4240762.

It is an arithmetic number, because the mean of its divisors is an integer number (5988890880).

Almost surely, 2^81968635348 is an apocalyptic number.

It is an amenable number.

81968635348 is a deficient number, since it is larger than the sum of its proper divisors (61764745772).

81968635348 is a wasteful number, since it uses less digits than its factorization.

81968635348 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21447 (or 21445 counting only the distinct ones).

The product of its digits is 29859840, while the sum is 61.

The spelling of 81968635348 in words is "eighty-one billion, nine hundred sixty-eight million, six hundred thirty-five thousand, three hundred forty-eight".