91244421 has 16 divisors (see below), whose sum is σ = 135425920. Its totient is φ = 60717600.

The previous prime is 91244407. The next prime is 91244459. The reversal of 91244421 is 12444219.

It is a happy number.

It is not a de Polignac number, because 91244421 - 2¹¹ = 91242373 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91244221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13416 + ... + 19038.

It is an arithmetic number, because the mean of its divisors is an integer number (8464120).

Almost surely, 2^91244421 is an apocalyptic number.

It is an amenable number.

91244421 is a deficient number, since it is larger than the sum of its proper divisors (44181499).

91244421 is a wasteful number, since it uses less digits than its factorization.

91244421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6233 (or 6227 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 91244421 is about 9552.1945646014. The cubic root of 91244421 is about 450.1964919673.

The spelling of 91244421 in words is "ninety-one million, two hundred forty-four thousand, four hundred twenty-one".