10001220 has 96 divisors (see below), whose sum is σ = 30535680. Its totient is φ = 2436480.

The previous prime is 10001213. The next prime is 10001221. The reversal of 10001220 is 2210001.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a junction number, because it is equal to n+sod(n) for n = 10001199 and 10001208.

It is not an unprimeable number, because it can be changed into a prime (10001221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35199 + ... + 35481.

It is an arithmetic number, because the mean of its divisors is an integer number (318080).

Almost surely, 2^10001220 is an apocalyptic number.

10001220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 10001220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15267840).

10001220 is an abundant number, since it is smaller than the sum of its proper divisors (20534460).

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

10001220 is a wasteful number, since it uses less digits than its factorization.

10001220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345 (or 343 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 10001220 is about 3162.4705532226. The cubic root of 10001220 is about 215.4522300147.

Adding to 10001220 its reverse (2210001), we get a palindrome (12211221).

The spelling of 10001220 in words is "ten million, one thousand, two hundred twenty".