10202123021 has 4 divisors (see below), whose sum is σ = 10202600700. Its totient is φ = 10201645344.

The previous prime is 10202123003. The next prime is 10202123027. The reversal of 10202123021 is 12032120201.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6907936996 + 3294186025 = 83114^2 + 57395^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10202123021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10202122987 and 10202123005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10202123027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205226 + ... + 250043.

It is an arithmetic number, because the mean of its divisors is an integer number (2550650175).

Almost surely, 2^10202123021 is an apocalyptic number.

It is an amenable number.

10202123021 is a deficient number, since it is larger than the sum of its proper divisors (477679).

10202123021 is an equidigital number, since it uses as much as digits as its factorization.

10202123021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477678.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 10202123021 its reverse (12032120201), we get a palindrome (22234243222).

The spelling of 10202123021 in words is "ten billion, two hundred two million, one hundred twenty-three thousand, twenty-one".