91869605 has 4 divisors (see below), whose sum is σ = 110243532. Its totient is φ = 73495680.

The previous prime is 91869601. The next prime is 91869619. The reversal of 91869605 is 50696819.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50696819 = 3769 ⋅13451.

It can be written as a sum of positive squares in 2 ways, for example, as 51394561 + 40475044 = 7169^2 + 6362^2 .

It is not a de Polignac number, because 91869605 - 2² = 91869601 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91869601) 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, 9186956 + ... + 9186965.

It is an arithmetic number, because the mean of its divisors is an integer number (27560883).

Almost surely, 2^91869605 is an apocalyptic number.

It is an amenable number.

91869605 is a deficient number, since it is larger than the sum of its proper divisors (18373927).

91869605 is a wasteful number, since it uses less digits than its factorization.

91869605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18373926.

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 91869605 is about 9584.8633271424. The cubic root of 91869605 is about 451.2223638510. Note that the first 3 decimals are identical.

The spelling of 91869605 in words is "ninety-one million, eight hundred sixty-nine thousand, six hundred five".