91487185633 has 4 divisors (see below), whose sum is σ = 91487832340. Its totient is φ = 91486538928.

The previous prime is 91487185591. The next prime is 91487185649. The reversal of 91487185633 is 33658178419.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 44018977249 + 47468208384 = 209807^2 + 217872^2 .

It is a cyclic number.

It is not a de Polignac number, because 91487185633 - 2⁹ = 91487185121 is a prime.

It is a super-2 number, since 2×91487185633² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91487185733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9810 + ... + 427867.

It is an arithmetic number, because the mean of its divisors is an integer number (22871958085).

Almost surely, 2^91487185633 is an apocalyptic number.

It is an amenable number.

91487185633 is a deficient number, since it is larger than the sum of its proper divisors (646707).

91487185633 is a wasteful number, since it uses less digits than its factorization.

91487185633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646706.

The product of its digits is 4354560, while the sum is 55.

The spelling of 91487185633 in words is "ninety-one billion, four hundred eighty-seven million, one hundred eighty-five thousand, six hundred thirty-three".