91118151807649 has 4 divisors (see below), whose sum is σ = 91125362246164. Its totient is φ = 91110941369136.

The previous prime is 91118151807643. The next prime is 91118151807673. The reversal of 91118151807649 is 94670815181119.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 31988695781025 + 59129456026624 = 5655855^2 + 7689568^2 .

It is a cyclic number.

It is not a de Polignac number, because 91118151807649 - 2¹⁷ = 91118151676577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91118151807643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3605200302 + ... + 3605225575.

It is an arithmetic number, because the mean of its divisors is an integer number (22781340561541).

Almost surely, 2^{91118151807649} is an apocalyptic number.

It is an amenable number.

91118151807649 is a deficient number, since it is larger than the sum of its proper divisors (7210438515).

91118151807649 is a wasteful number, since it uses less digits than its factorization.

91118151807649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7210438514.

The product of its (nonzero) digits is 4354560, while the sum is 61.

The spelling of 91118151807649 in words is "ninety-one trillion, one hundred eighteen billion, one hundred fifty-one million, eight hundred seven thousand, six hundred forty-nine".