91686137 has 2 divisors, whose sum is σ = 91686138. Its totient is φ = 91686136.

The previous prime is 91686121. The next prime is 91686157. The reversal of 91686137 is 73168619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70627216 + 21058921 = 8404^2 + 4589^2 .

It is a cyclic number.

It is not a de Polignac number, because 91686137 - 2⁴ = 91686121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91686094 and 91686103.

It is not a weakly prime, because it can be changed into another prime (91686157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45843068 + 45843069.

It is an arithmetic number, because the mean of its divisors is an integer number (45843069).

Almost surely, 2^91686137 is an apocalyptic number.

It is an amenable number.

91686137 is a deficient number, since it is larger than the sum of its proper divisors (1).

91686137 is an equidigital number, since it uses as much as digits as its factorization.

91686137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 41.

The square root of 91686137 is about 9575.2878285720. The cubic root of 91686137 is about 450.9217927887.

The spelling of 91686137 in words is "ninety-one million, six hundred eighty-six thousand, one hundred thirty-seven".