91729489640 has 32 divisors (see below), whose sum is σ = 215364890880. Its totient is φ = 35096500032.

The previous prime is 91729489613. The next prime is 91729489681. The reversal of 91729489640 is 4698492719.

It is a super-2 number, since 2×91729489640² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91729489640.

It is an unprimeable number.

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, 49852064 + ... + 49853903.

It is an arithmetic number, because the mean of its divisors is an integer number (6730152840).

Almost surely, 2^91729489640 is an apocalyptic number.

It is an amenable number.

91729489640 is an abundant number, since it is smaller than the sum of its proper divisors (123635401240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91729489640 is a wasteful number, since it uses less digits than its factorization.

91729489640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99706001 (or 99705997 counting only the distinct ones).

The product of its (nonzero) digits is 7838208, while the sum is 59.

The spelling of 91729489640 in words is "ninety-one billion, seven hundred twenty-nine million, four hundred eighty-nine thousand, six hundred forty".