81744837967 has 16 divisors (see below), whose sum is σ = 95655454720. Its totient is φ = 69179378400.

The previous prime is 81744837917. The next prime is 81744837997. The reversal of 81744837967 is 76973844718.

It is a cyclic number.

It is not a de Polignac number, because 81744837967 - 2¹⁵ = 81744805199 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81744837899 and 81744837908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81744837917) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5330259 + ... + 5345572.

It is an arithmetic number, because the mean of its divisors is an integer number (5978465920).

Almost surely, 2^81744837967 is an apocalyptic number.

81744837967 is a deficient number, since it is larger than the sum of its proper divisors (13910616753).

81744837967 is a wasteful number, since it uses less digits than its factorization.

81744837967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10675894.

The product of its digits is 56899584, while the sum is 64.

The spelling of 81744837967 in words is "eighty-one billion, seven hundred forty-four million, eight hundred thirty-seven thousand, nine hundred sixty-seven".