91206145 has 4 divisors (see below), whose sum is σ = 109447380. Its totient is φ = 72964912.

The previous prime is 91206133. The next prime is 91206149. The reversal of 91206145 is 54160219.

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 57577744 + 33628401 = 7588^2 + 5799^2 .

It is a cyclic number.

It is not a de Polignac number, because 91206145 - 2¹¹ = 91204097 is a prime.

It is a super-2 number, since 2×91206145² = 16637121771522050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91206149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9120610 + ... + 9120619.

It is an arithmetic number, because the mean of its divisors is an integer number (27361845).

Almost surely, 2^91206145 is an apocalyptic number.

It is an amenable number.

91206145 is a deficient number, since it is larger than the sum of its proper divisors (18241235).

91206145 is a wasteful number, since it uses less digits than its factorization.

91206145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18241234.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 91206145 is about 9550.1908357896. The cubic root of 91206145 is about 450.1335323883.

The spelling of 91206145 in words is "ninety-one million, two hundred six thousand, one hundred forty-five".