91729786 has 4 divisors (see below), whose sum is σ = 137594682. Its totient is φ = 45864892.

The previous prime is 91729783. The next prime is 91729811. The reversal of 91729786 is 68792719.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 68792719 = 67 ⋅1026757.

It can be written as a sum of positive squares in only one way, i.e., 91565761 + 164025 = 9569^2 + 405^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (91729783) 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 as a sum of consecutive naturals, namely, 22932445 + ... + 22932448.

Almost surely, 2^91729786 is an apocalyptic number.

91729786 is a deficient number, since it is larger than the sum of its proper divisors (45864896).

91729786 is a wasteful number, since it uses less digits than its factorization.

91729786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45864895.

The product of its digits is 381024, while the sum is 49.

The square root of 91729786 is about 9577.5668099993. The cubic root of 91729786 is about 450.9933381841.

It can be divided in two parts, 917 and 29786, that added together give a palindrome (30703).

The spelling of 91729786 in words is "ninety-one million, seven hundred twenty-nine thousand, seven hundred eighty-six".