91721740742 has 8 divisors (see below), whose sum is σ = 141301060176. Its totient is φ = 44621387352.

The previous prime is 91721740727. The next prime is 91721740787. The reversal of 91721740742 is 24704712719.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 91721740693 and 91721740702.

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, 619741418 + ... + 619741565.

It is an arithmetic number, because the mean of its divisors is an integer number (17662632522).

Almost surely, 2^91721740742 is an apocalyptic number.

91721740742 is a deficient number, since it is larger than the sum of its proper divisors (49579319434).

91721740742 is a wasteful number, since it uses less digits than its factorization.

91721740742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1239483022.

The product of its (nonzero) digits is 197568, while the sum is 44.

The spelling of 91721740742 in words is "ninety-one billion, seven hundred twenty-one million, seven hundred forty thousand, seven hundred forty-two".