91181049444 has 81 divisors (see below), whose sum is σ = 234733360953. Its totient is φ = 29843508384.

The previous prime is 91181049409. The next prime is 91181049469. The reversal of 91181049444 is 44494018119.

It is a happy number.

The square root of 91181049444 is 301962.

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

91181049444 is a `hidden beast` number, since 9 + 118 + 1 + 0 + 494 + 44 = 666.

It can be written as a sum of positive squares in only one way, i.e., 5266404900 + 85914644544 = 72570^2 + 293112^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 91181049444.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 106894122 + ... + 106894974.

Almost surely, 2^91181049444 is an apocalyptic number.

91181049444 is the 301962-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91181049444

91181049444 is an abundant number, since it is smaller than the sum of its proper divisors (143552311509).

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

91181049444 is an equidigital number, since it uses as much as digits as its factorization.

91181049444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1834 (or 917 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 91181049444 in words is "ninety-one billion, one hundred eighty-one million, forty-nine thousand, four hundred forty-four".