91040061 has 32 divisors (see below), whose sum is σ = 142518528. Its totient is φ = 50618880.

The previous prime is 91040057. The next prime is 91040071. The reversal of 91040061 is 16004019.

It is not a de Polignac number, because 91040061 - 2² = 91040057 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91040041) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 174481 + ... + 175001.

It is an arithmetic number, because the mean of its divisors is an integer number (4453704).

Almost surely, 2^91040061 is an apocalyptic number.

It is an amenable number.

91040061 is a deficient number, since it is larger than the sum of its proper divisors (51478467).

91040061 is a wasteful number, since it uses less digits than its factorization.

91040061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 741.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 91040061 is about 9541.4915500670. The cubic root of 91040061 is about 449.8601392516.

The spelling of 91040061 in words is "ninety-one million, forty thousand, sixty-one".