91081522544896 has 243 divisors, whose sum is σ = 209207415172791. Its totient is φ = 39550165204992.

The previous prime is 91081522544891. The next prime is 91081522545011. The reversal of 91081522544896 is 69844522518019.

The square root of 91081522544896 is 9543664.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 822402314496 + 90259120230400 = 906864^2 + 9500480^2 .

It is a Harshad number since it is a multiple of its sum of digits (64).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91081522544891) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 33746394555 + ... + 33746397253.

Almost surely, 2^{91081522544896} is an apocalyptic number.

91081522544896 is the 9543664-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91081522544896

91081522544896 is an abundant number, since it is smaller than the sum of its proper divisors (118125892627895).

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

91081522544896 is an frugal number, since it uses more digits than its factorization.

91081522544896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5474 (or 2731 counting only the distinct ones).

The product of its (nonzero) digits is 49766400, while the sum is 64.

91081522544896 divided by its sum of digits (64) gives a square (1423148789764 = 1192958²).

The spelling of 91081522544896 in words is "ninety-one trillion, eighty-one billion, five hundred twenty-two million, five hundred forty-four thousand, eight hundred ninety-six".