91050221 has 4 divisors (see below), whose sum is σ = 93167712. Its totient is φ = 88932732.

The previous prime is 91050209. The next prime is 91050241. The reversal of 91050221 is 12205019.

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: 12205019 = 23 ⋅530653.

It is a cyclic number.

It is not a de Polignac number, because 91050221 - 2¹⁴ = 91033837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91050193 and 91050202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91050241) 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, 1058681 + ... + 1058766.

It is an arithmetic number, because the mean of its divisors is an integer number (23291928).

Almost surely, 2^91050221 is an apocalyptic number.

It is an amenable number.

91050221 is a deficient number, since it is larger than the sum of its proper divisors (2117491).

91050221 is a wasteful number, since it uses less digits than its factorization.

91050221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2117490.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 91050221 is about 9542.0239467316. The cubic root of 91050221 is about 449.8768733097.

The spelling of 91050221 in words is "ninety-one million, fifty thousand, two hundred twenty-one".