91221700 has 18 divisors (see below), whose sum is σ = 197951306. Its totient is φ = 36488640.

The previous prime is 91221671. The next prime is 91221721. The reversal of 91221700 is 712219.

It can be written as a sum of positive squares in 3 ways, for example, as 6728836 + 84492864 = 2594^2 + 9192^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 456009 + ... + 456208.

Almost surely, 2^91221700 is an apocalyptic number.

It is an amenable number.

91221700 is an abundant number, since it is smaller than the sum of its proper divisors (106729606).

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

91221700 is a wasteful number, since it uses less digits than its factorization.

91221700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912231 (or 912224 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 91221700 is about 9551.0051827020. The cubic root of 91221700 is about 450.1591206828.

Adding to 91221700 its reverse (712219), we get a palindrome (91933919).

The spelling of 91221700 in words is "ninety-one million, two hundred twenty-one thousand, seven hundred".