1001211101220 has 192 divisors, whose sum is σ = 3238956999936. Its totient is φ = 228382801920.

The previous prime is 1001211101183. The next prime is 1001211101221. The reversal of 1001211101220 is 221011121001.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 1001211101196 and 1001211101205.

It is not an unprimeable number, because it can be changed into a prime (1001211101221) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 57808002 + ... + 57825318.

It is an arithmetic number, because the mean of its divisors is an integer number (16869567708).

Almost surely, 2^{1001211101220} is an apocalyptic number.

1001211101220 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 1001211101220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1619478499968).

1001211101220 is an abundant number, since it is smaller than the sum of its proper divisors (2237745898716).

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

1001211101220 is a wasteful number, since it uses less digits than its factorization.

1001211101220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22510 (or 22508 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 1001211101220 its reverse (221011121001), we get a palindrome (1222222222221).

The spelling of 1001211101220 in words is "one trillion, one billion, two hundred eleven million, one hundred one thousand, two hundred twenty".