2001012021000 has 192 divisors, whose sum is σ = 6768925890480. Its totient is φ = 533168870400.

The previous prime is 2001012020999. The next prime is 2001012021103. The reversal of 2001012021000 is 1202101002.

It can be written as a sum of positive squares in 8 ways, for example, as 392219123076 + 1608792897924 = 626274^2 + 1268382^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11043132 + ... + 11222868.

Almost surely, 2^{2001012021000} is an apocalyptic number.

2001012021000 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 2001012021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3384462945240).

2001012021000 is an abundant number, since it is smaller than the sum of its proper divisors (4767913869480).

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

2001012021000 is a wasteful number, since it uses less digits than its factorization.

2001012021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181001 (or 180984 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 2001012021000 its reverse (1202101002), we get a palindrome (2002214122002).

The spelling of 2001012021000 in words is "two trillion, one billion, twelve million, twenty-one thousand".