91693451520 has 540 divisors, whose sum is σ = 360683718780. Its totient is φ = 22225674240.

The previous prime is 91693451483. The next prime is 91693451533. The reversal of 91693451520 is 2515439619.

91693451520 is a `hidden beast` number, since 91 + 6 + 9 + 34 + 5 + 1 + 520 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 36735088896 + 54958362624 = 191664^2 + 234432^2 .

It is a tau number, because it is divible by the number of its divisors (540).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 12541626 + ... + 12548934.

Almost surely, 2^91693451520 is an apocalyptic number.

91693451520 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 91693451520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180341859390).

91693451520 is an abundant number, since it is smaller than the sum of its proper divisors (268990267260).

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

91693451520 is a wasteful number, since it uses less digits than its factorization.

91693451520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7364 (or 7330 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The spelling of 91693451520 in words is "ninety-one billion, six hundred ninety-three million, four hundred fifty-one thousand, five hundred twenty".