91747977 has 16 divisors (see below), whose sum is σ = 124035648. Its totient is φ = 60318720.

The previous prime is 91747949. The next prime is 91747987. The reversal of 91747977 is 77974719.

It is not a de Polignac number, because 91747977 - 2¹² = 91743881 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91747987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81138 + ... + 82260.

It is an arithmetic number, because the mean of its divisors is an integer number (7752228).

Almost surely, 2^91747977 is an apocalyptic number.

It is an amenable number.

91747977 is a deficient number, since it is larger than the sum of its proper divisors (32287671).

91747977 is a wasteful number, since it uses less digits than its factorization.

91747977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1480.

The product of its digits is 777924, while the sum is 51.

The square root of 91747977 is about 9578.5164300115. The cubic root of 91747977 is about 451.0231484850.

The spelling of 91747977 in words is "ninety-one million, seven hundred forty-seven thousand, nine hundred seventy-seven".