91055591 has 8 divisors (see below), whose sum is σ = 101447424. Its totient is φ = 81016120.

The previous prime is 91055579. The next prime is 91055593. The reversal of 91055591 is 19555019.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91055591 - 2⁶ = 91055527 is a prime.

It is a super-2 number, since 2×91055591² = 16582241304718562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91055593) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 87545 + ... + 88578.

It is an arithmetic number, because the mean of its divisors is an integer number (12680928).

Almost surely, 2^91055591 is an apocalyptic number.

91055591 is a deficient number, since it is larger than the sum of its proper divisors (10391833).

91055591 is a wasteful number, since it uses less digits than its factorization.

91055591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176181.

The product of its (nonzero) digits is 10125, while the sum is 35.

The square root of 91055591 is about 9542.3053294264. The cubic root of 91055591 is about 449.8857174812.

The spelling of 91055591 in words is "ninety-one million, fifty-five thousand, five hundred ninety-one".