10002020121 has 6 divisors (see below), whose sum is σ = 14447362410. Its totient is φ = 6668013408.

The previous prime is 10002020113. The next prime is 10002020131. The reversal of 10002020121 is 12102020001.

10002020121 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 8730099225 + 1271920896 = 93435^2 + 35664^2 .

It is not a de Polignac number, because 10002020121 - 2³ = 10002020113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 1111335569 = 10002020121 / (1 + 0 + 0 + 0 + 2 + 0 + 2 + 0 + 1 + 2 + 1).

It is not an unprimeable number, because it can be changed into a prime (10002020101) 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, 555667776 + ... + 555667793.

It is an arithmetic number, because the mean of its divisors is an integer number (2407893735).

Almost surely, 2^10002020121 is an apocalyptic number.

It is an amenable number.

10002020121 is a deficient number, since it is larger than the sum of its proper divisors (4445342289).

10002020121 is a wasteful number, since it uses less digits than its factorization.

10002020121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111335575 (or 1111335572 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 10002020121 its reverse (12102020001), we get a palindrome (22104040122).

The spelling of 10002020121 in words is "ten billion, two million, twenty thousand, one hundred twenty-one".