21121121002020 has 96 divisors (see below), whose sum is σ = 63693240885120. Its totient is φ = 5198642104320.

The previous prime is 21121121002013. The next prime is 21121121002027. The reversal of 21121121002020 is 2020012112112.

It is an interprime number because it is at equal distance from previous prime (21121121002013) and next prime (21121121002027).

It is a super-2 number, since 2×21121121002020² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (21121121002027) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 9080460 + ... + 11166780.

It is an arithmetic number, because the mean of its divisors is an integer number (663471259220).

Almost surely, 2^{21121121002020} is an apocalyptic number.

21121121002020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121121002020 is an abundant number, since it is smaller than the sum of its proper divisors (42572119883100).

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

21121121002020 is a wasteful number, since it uses less digits than its factorization.

21121121002020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2099325 (or 2099323 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21121121002020 its reverse (2020012112112), we get a palindrome (23141133114132).

The spelling of 21121121002020 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty-one million, two thousand, twenty".