20112121001 has 6 divisors (see below), whose sum is σ = 23395732650. Its totient is φ = 17238960816.

The previous prime is 20112120983. The next prime is 20112121019. The reversal of 20112121001 is 10012121102.

It is an interprime number because it is at equal distance from previous prime (20112120983) and next prime (20112121019).

It can be written as a sum of positive squares in only one way, i.e., 20079173401 + 32947600 = 141701^2 + 5740^2 .

It is not a de Polignac number, because 20112121001 - 2⁶ = 20112120937 is a prime.

It is a super-2 number, since 2×20112121001² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20112121501) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 205225676 + ... + 205225773.

It is an arithmetic number, because the mean of its divisors is an integer number (3899288775).

Almost surely, 2^20112121001 is an apocalyptic number.

It is an amenable number.

20112121001 is a deficient number, since it is larger than the sum of its proper divisors (3283611649).

20112121001 is an equidigital number, since it uses as much as digits as its factorization.

20112121001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410451463 (or 410451456 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 20112121001 its reverse (10012121102), we get a palindrome (30124242103).

The spelling of 20112121001 in words is "twenty billion, one hundred twelve million, one hundred twenty-one thousand, one".