91820101 has 4 divisors (see below), whose sum is σ = 91858752. Its totient is φ = 91781452.

The previous prime is 91820087. The next prime is 91820123. The reversal of 91820101 is 10102819.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10102819 = 23 ⋅439253.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91820101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91820501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15511 + ... + 20596.

It is an arithmetic number, because the mean of its divisors is an integer number (22964688).

Almost surely, 2^91820101 is an apocalyptic number.

It is an amenable number.

91820101 is a deficient number, since it is larger than the sum of its proper divisors (38651).

91820101 is a wasteful number, since it uses less digits than its factorization.

91820101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38650.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 91820101 is about 9582.2805740596. The cubic root of 91820101 is about 451.1413021286.

The spelling of 91820101 in words is "ninety-one million, eight hundred twenty thousand, one hundred one".