91720606 has 8 divisors (see below), whose sum is σ = 137864880. Its totient is φ = 45765648.

The previous prime is 91720597. The next prime is 91720609. The reversal of 91720606 is 60602719.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91720609) 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 3 ways as a sum of consecutive naturals, for example, 46111 + ... + 48058.

It is an arithmetic number, because the mean of its divisors is an integer number (17233110).

Almost surely, 2^91720606 is an apocalyptic number.

91720606 is a deficient number, since it is larger than the sum of its proper divisors (46144274).

91720606 is a wasteful number, since it uses less digits than its factorization.

91720606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94658.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 91720606 is about 9577.0875531134. The cubic root of 91720606 is about 450.9782930639.

The spelling of 91720606 in words is "ninety-one million, seven hundred twenty thousand, six hundred six".