91213842720 has 1152 divisors, whose sum is σ = 411192391680. Its totient is φ = 16447242240.

The previous prime is 91213842691. The next prime is 91213842743. The reversal of 91213842720 is 2724831219.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 106185651 + ... + 106186509.

It is an arithmetic number, because the mean of its divisors is an integer number (356937840).

Almost surely, 2^91213842720 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 91213842720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (205596195840).

91213842720 is an abundant number, since it is smaller than the sum of its proper divisors (319978548960).

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

91213842720 is a wasteful number, since it uses less digits than its factorization.

91213842720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 938 (or 917 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 39.

The spelling of 91213842720 in words is "ninety-one billion, two hundred thirteen million, eight hundred forty-two thousand, seven hundred twenty".