20111021000 has 192 divisors, whose sum is σ = 54990439920. Its totient is φ = 6864076800.

The previous prime is 20111020957. The next prime is 20111021023. The reversal of 20111021000 is 12011102.

It can be written as a sum of positive squares in 8 ways, for example, as 2358656356 + 17752364644 = 48566^2 + 133238^2 .

It is a Harshad number since it is a multiple of its sum of digits (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 12592202 + ... + 12593798.

Almost surely, 2^20111021000 is an apocalyptic number.

20111021000 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 20111021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27495219960).

20111021000 is an abundant number, since it is smaller than the sum of its proper divisors (34879418920).

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

20111021000 is a wasteful number, since it uses less digits than its factorization.

20111021000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1889 (or 1868 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 20111021000 its reverse (12011102), we get a palindrome (20123032102).

It can be divided in two parts, 2011102 and 1000, that added together give a palindrome (2012102).

The spelling of 20111021000 in words is "twenty billion, one hundred eleven million, twenty-one thousand".