91024220 has 48 divisors (see below), whose sum is σ = 219360960. Its totient is φ = 31079424.

The previous prime is 91024189. The next prime is 91024229. The reversal of 91024220 is 2242019.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 91024192 and 91024201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91024229) 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, 36452 + ... + 38868.

It is an arithmetic number, because the mean of its divisors is an integer number (4570020).

Almost surely, 2^91024220 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91024220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109680480).

91024220 is an abundant number, since it is smaller than the sum of its proper divisors (128336740).

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

91024220 is a wasteful number, since it uses less digits than its factorization.

91024220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2702 (or 2700 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 91024220 is about 9540.6614026492. The cubic root of 91024220 is about 449.8340458016.

Adding to 91024220 its reverse (2242019), we get a palindrome (93266239).

The spelling of 91024220 in words is "ninety-one million, twenty-four thousand, two hundred twenty".