91222068777840 has 2560 divisors, whose sum is σ = 434145012940800. Its totient is φ = 16990189240320.

The previous prime is 91222068777839. The next prime is 91222068777871. The reversal of 91222068777840 is 4877786022219.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 511 ways as a sum of consecutive naturals, for example, 59119940109 + ... + 59119941651.

It is an arithmetic number, because the mean of its divisors is an integer number (169587895680).

Almost surely, 2^{91222068777840} is an apocalyptic number.

91222068777840 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91222068777840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217072506470400).

91222068777840 is an abundant number, since it is smaller than the sum of its proper divisors (342922944162960).

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

91222068777840 is a wasteful number, since it uses less digits than its factorization.

91222068777840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2372 (or 2360 counting only the distinct ones).

The product of its (nonzero) digits is 37933056, while the sum is 63.

The spelling of 91222068777840 in words is "ninety-one trillion, two hundred twenty-two billion, sixty-eight million, seven hundred seventy-seven thousand, eight hundred forty".