20021120121 has 16 divisors (see below), whose sum is σ = 27410872320. Its totient is φ = 12993784080.

The previous prime is 20021120117. The next prime is 20021120143. The reversal of 20021120121 is 12102112002.

It is not a de Polignac number, because 20021120121 - 2² = 20021120117 is a prime.

It is a super-2 number, since 2×20021120121² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20021120097 and 20021120106.

It is not an unprimeable number, because it can be changed into a prime (20021120191) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 530865 + ... + 567326.

It is an arithmetic number, because the mean of its divisors is an integer number (1713179520).

Almost surely, 2^20021120121 is an apocalyptic number.

It is an amenable number.

20021120121 is a deficient number, since it is larger than the sum of its proper divisors (7389752199).

20021120121 is a wasteful number, since it uses less digits than its factorization.

20021120121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098356.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 20021120121 its reverse (12102112002), we get a palindrome (32123232123).

The spelling of 20021120121 in words is "twenty billion, twenty-one million, one hundred twenty thousand, one hundred twenty-one".