1001001221010 has 384 divisors, whose sum is σ = 3189834086400. Its totient is φ = 212695372800.

The previous prime is 1001001220979. The next prime is 1001001221081. The reversal of 1001001221010 is 101221001001.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1001001220983 and 1001001221001.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 555802110 + ... + 555803910.

It is an arithmetic number, because the mean of its divisors is an integer number (8306859600).

Almost surely, 2^{1001001221010} is an apocalyptic number.

1001001221010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1001001221010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1594917043200).

1001001221010 is an abundant number, since it is smaller than the sum of its proper divisors (2188832865390).

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

1001001221010 is a wasteful number, since it uses less digits than its factorization.

1001001221010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2686 (or 2683 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 1001001221010 its reverse (101221001001), we get a palindrome (1102222222011).

The spelling of 1001001221010 in words is "one trillion, one billion, one million, two hundred twenty-one thousand, ten".