91728211367520 has 960 divisors, whose sum is σ = 400968296378496. Its totient is φ = 19230334156800.

The previous prime is 91728211367473. The next prime is 91728211367537. The reversal of 91728211367520 is 2576311282719.

91728211367520 is a `hidden beast` number, since 9 + 1 + 7 + 2 + 82 + 1 + 1 + 36 + 7 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 184911820 + ... + 185407220.

Almost surely, 2^{91728211367520} is an apocalyptic number.

91728211367520 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 91728211367520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200484148189248).

91728211367520 is an abundant number, since it is smaller than the sum of its proper divisors (309240085010976).

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

91728211367520 is a wasteful number, since it uses less digits than its factorization.

91728211367520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495605 (or 495588 counting only the distinct ones).

The product of its (nonzero) digits is 2540160, while the sum is 54.

The spelling of 91728211367520 in words is "ninety-one trillion, seven hundred twenty-eight billion, two hundred eleven million, three hundred sixty-seven thousand, five hundred twenty".