1001001220 has 12 divisors (see below), whose sum is σ = 2102102604. Its totient is φ = 400400480.

The previous prime is 1001001217. The next prime is 1001001223. The reversal of 1001001220 is 221001001.

It is an interprime number because it is at equal distance from previous prime (1001001217) and next prime (1001001223).

It can be written as a sum of positive squares in 2 ways, for example, as 304991296 + 696009924 = 17464^2 + 26382^2 .

It is not an unprimeable number, because it can be changed into a prime (1001001223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25025011 + ... + 25025050.

It is an arithmetic number, because the mean of its divisors is an integer number (175175217).

Almost surely, 2^1001001220 is an apocalyptic number.

1001001220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001001220 is an abundant number, since it is smaller than the sum of its proper divisors (1101101384).

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

1001001220 is a wasteful number, since it uses less digits than its factorization.

1001001220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50050070 (or 50050068 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 1001001220 is about 31638.6033193629. The cubic root of 1001001220 is about 1000.3336286795. Note that the first 3 decimals are identical.

Adding to 1001001220 its reverse (221001001), we get a palindrome (1222002221).

The spelling of 1001001220 in words is "one billion, one million, one thousand, two hundred twenty".