203120300021 has 4 divisors (see below), whose sum is σ = 203123186700. Its totient is φ = 203117413344.

The previous prime is 203120299981. The next prime is 203120300051. The reversal of 203120300021 is 120003021302.

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 78430803025 + 124689496996 = 280055^2 + 353114^2 .

It is a cyclic number.

It is not a de Polignac number, because 203120300021 - 2²⁶ = 203053191157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 203120299969 and 203120300005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (203120300051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1335086 + ... + 1479423.

It is an arithmetic number, because the mean of its divisors is an integer number (50780796675).

Almost surely, 2^203120300021 is an apocalyptic number.

It is an amenable number.

203120300021 is a deficient number, since it is larger than the sum of its proper divisors (2886679).

203120300021 is an equidigital number, since it uses as much as digits as its factorization.

203120300021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2886678.

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 203120300021 its reverse (120003021302), we get a palindrome (323123321323).

The spelling of 203120300021 in words is "two hundred three billion, one hundred twenty million, three hundred thousand, twenty-one".