91017620 has 24 divisors (see below), whose sum is σ = 191909088. Its totient is φ = 36260000.

The previous prime is 91017613. The next prime is 91017623. The reversal of 91017620 is 2671019.

It is a self number, because there is not a number n which added to its sum of digits gives 91017620.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91017623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4046 + ... + 14085.

It is an arithmetic number, because the mean of its divisors is an integer number (7996212).

Almost surely, 2^91017620 is an apocalyptic number.

It is an amenable number.

91017620 is an abundant number, since it is smaller than the sum of its proper divisors (100891468).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91017620 is a wasteful number, since it uses less digits than its factorization.

91017620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18391 (or 18389 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 91017620 is about 9540.3155084096. The cubic root of 91017620 is about 449.8231733237.

Adding to 91017620 its reverse (2671019), we get a palindrome (93688639).

The spelling of 91017620 in words is "ninety-one million, seventeen thousand, six hundred twenty".