2001011001220 has 192 divisors, whose sum is σ = 5314348892160. Its totient is φ = 614749824000.

The previous prime is 2001011001193. The next prime is 2001011001259. The reversal of 2001011001220 is 221001101002.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 2001011001197 and 2001011001206.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 73103977 + ... + 73131343.

It is an arithmetic number, because the mean of its divisors is an integer number (27678900480).

Almost surely, 2^{2001011001220} is an apocalyptic number.

2001011001220 is a gapful number since it is divisible by the number (20) 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 2001011001220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2657174446080).

2001011001220 is an abundant number, since it is smaller than the sum of its proper divisors (3313337890940).

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

2001011001220 is a wasteful number, since it uses less digits than its factorization.

2001011001220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28074 (or 28072 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 2001011001220 its reverse (221001101002), we get a palindrome (2222012102222).

The spelling of 2001011001220 in words is "two trillion, one billion, eleven million, one thousand, two hundred twenty".