81996157694 has 16 divisors (see below), whose sum is σ = 134870747760. Its totient is φ = 37077864960.

The previous prime is 81996157687. The next prime is 81996157697. The reversal of 81996157694 is 49675169918.

It is a self number, because there is not a number n which added to its sum of digits gives 81996157694.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81996157697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9651449 + ... + 9659940.

It is an arithmetic number, because the mean of its divisors is an integer number (8429421735).

Almost surely, 2^81996157694 is an apocalyptic number.

81996157694 is a deficient number, since it is larger than the sum of its proper divisors (52874590066).

81996157694 is a wasteful number, since it uses less digits than its factorization.

81996157694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19311595.

The product of its digits is 29393280, while the sum is 65.

The spelling of 81996157694 in words is "eighty-one billion, nine hundred ninety-six million, one hundred fifty-seven thousand, six hundred ninety-four".