81683297648 has 20 divisors (see below), whose sum is σ = 160943787480. Its totient is φ = 40149417024.

The previous prime is 81683297609. The next prime is 81683297743. The reversal of 81683297648 is 84679238618.

It is a super-2 number, since 2×81683297648² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (62) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43263515 + ... + 43265402.

It is an arithmetic number, because the mean of its divisors is an integer number (8047189374).

Almost surely, 2^81683297648 is an apocalyptic number.

It is an amenable number.

81683297648 is a deficient number, since it is larger than the sum of its proper divisors (79260489832).

81683297648 is a wasteful number, since it uses less digits than its factorization.

81683297648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86528984 (or 86528978 counting only the distinct ones).

The product of its digits is 27869184, while the sum is 62.

The spelling of 81683297648 in words is "eighty-one billion, six hundred eighty-three million, two hundred ninety-seven thousand, six hundred forty-eight".