91658550720 has 448 divisors, whose sum is σ = 330105715200. Its totient is φ = 21344010240.

The previous prime is 91658550719. The next prime is 91658550779. The reversal of 91658550720 is 2705585619.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 91658550720.

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 70128307 + ... + 70129613.

Almost surely, 2^91658550720 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91658550720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (165052857600).

91658550720 is an abundant number, since it is smaller than the sum of its proper divisors (238447164480).

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

91658550720 is a wasteful number, since it uses less digits than its factorization.

91658550720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1596 (or 1586 counting only the distinct ones).

The product of its (nonzero) digits is 756000, while the sum is 48.

The spelling of 91658550720 in words is "ninety-one billion, six hundred fifty-eight million, five hundred fifty thousand, seven hundred twenty".