91911601 has 4 divisors (see below), whose sum is σ = 92725092. Its totient is φ = 91098112.

The previous prime is 91911581. The next prime is 91911629. The reversal of 91911601 is 10611919.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7290000 + 84621601 = 2700^2 + 9199^2 .

It is a cyclic number.

It is not a de Polignac number, because 91911601 - 2¹⁷ = 91780529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91911601.

It is not an unprimeable number, because it can be changed into a prime (91911641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 406576 + ... + 406801.

It is an arithmetic number, because the mean of its divisors is an integer number (23181273).

Almost surely, 2^91911601 is an apocalyptic number.

It is an amenable number.

91911601 is a deficient number, since it is larger than the sum of its proper divisors (813491).

91911601 is a wasteful number, since it uses less digits than its factorization.

91911601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 813490.

The product of its (nonzero) digits is 486, while the sum is 28.

The square root of 91911601 is about 9587.0538227341. The cubic root of 91911601 is about 451.2911085597.

The spelling of 91911601 in words is "ninety-one million, nine hundred eleven thousand, six hundred one".