1000001220 has 48 divisors (see below), whose sum is σ = 2875685568. Its totient is φ = 259459200.

The previous prime is 1000001213. The next prime is 1000001237. The reversal of 1000001220 is 221000001.

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 = 1000001199 and 1000001208.

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 15 ways as a sum of consecutive naturals, for example, 223006 + ... + 227445.

It is an arithmetic number, because the mean of its divisors is an integer number (59910116).

Almost surely, 2^1000001220 is an apocalyptic number.

1000001220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1000001220 is an abundant number, since it is smaller than the sum of its proper divisors (1875684348).

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

1000001220 is a wasteful number, since it uses less digits than its factorization.

1000001220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450500 (or 450498 counting only the distinct ones).

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

The square root of 1000001220 is about 31622.7958915716. The cubic root of 1000001220 is about 1000.0004066665. Note that the first 3 decimals are identical.

Adding to 1000001220 its reverse (221000001), we get a palindrome (1221001221).

The spelling of 1000001220 in words is "one billion, one thousand, two hundred twenty".