10120200021 has 20 divisors (see below), whose sum is σ = 15324932172. Its totient is φ = 6654374208.

The previous prime is 10120199983. The next prime is 10120200037. The reversal of 10120200021 is 12000202101.

It can be written as a sum of positive squares in 2 ways, for example, as 3734432100 + 6385767921 = 61110^2 + 79911^2 .

It is not a de Polignac number, because 10120200021 - 2¹⁴ = 10120183637 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 10120199976 and 10120200012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10120200091) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 849846 + ... + 861671.

Almost surely, 2^10120200021 is an apocalyptic number.

It is an amenable number.

10120200021 is a deficient number, since it is larger than the sum of its proper divisors (5204732151).

10120200021 is an equidigital number, since it uses as much as digits as its factorization.

10120200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1711602 (or 1711593 counting only the distinct ones).

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

Adding to 10120200021 its reverse (12000202101), we get a palindrome (22120402122).

The spelling of 10120200021 in words is "ten billion, one hundred twenty million, two hundred thousand, twenty-one".