91720712 has 32 divisors (see below), whose sum is σ = 182956320. Its totient is φ = 42958080.

The previous prime is 91720703. The next prime is 91720747. The reversal of 91720712 is 21702719.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29387 + ... + 32357.

It is an arithmetic number, because the mean of its divisors is an integer number (5717385).

Almost surely, 2^91720712 is an apocalyptic number.

It is an amenable number.

91720712 is a deficient number, since it is larger than the sum of its proper divisors (91235608).

91720712 is a wasteful number, since it uses less digits than its factorization.

91720712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3221 (or 3217 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 29.

The square root of 91720712 is about 9577.0930871533. The cubic root of 91720712 is about 450.9784667933.

The spelling of 91720712 in words is "ninety-one million, seven hundred twenty thousand, seven hundred twelve".