81744962091 has 32 divisors (see below), whose sum is σ = 121193533440. Its totient is φ = 48669897600.

The previous prime is 81744962081. The next prime is 81744962093. The reversal of 81744962091 is 19026944718.

It is not a de Polignac number, because 81744962091 - 2⁶ = 81744962027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81744962093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8590026 + ... + 8599536.

It is an arithmetic number, because the mean of its divisors is an integer number (3787297920).

Almost surely, 2^81744962091 is an apocalyptic number.

81744962091 is a deficient number, since it is larger than the sum of its proper divisors (39448571349).

81744962091 is a wasteful number, since it uses less digits than its factorization.

81744962091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16667.

The product of its (nonzero) digits is 870912, while the sum is 51.

The spelling of 81744962091 in words is "eighty-one billion, seven hundred forty-four million, nine hundred sixty-two thousand, ninety-one".