20021021201976 has 128 divisors (see below), whose sum is σ = 54299860876800. Its totient is φ = 6127050424320.

The previous prime is 20021021201903. The next prime is 20021021201977. The reversal of 20021021201976 is 67910212012002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021021201977) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12749341 + ... + 14233331.

It is an arithmetic number, because the mean of its divisors is an integer number (424217663100).

Almost surely, 2^{20021021201976} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20021021201976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27149930438400).

20021021201976 is an abundant number, since it is smaller than the sum of its proper divisors (34278839674824).

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

20021021201976 is a wasteful number, since it uses less digits than its factorization.

20021021201976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1484829 (or 1484825 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 33.

Adding to 20021021201976 its reverse (67910212012002), we get a palindrome (87931233213978).

The spelling of 20021021201976 in words is "twenty trillion, twenty-one billion, twenty-one million, two hundred one thousand, nine hundred seventy-six".