203003120921 has 2 divisors, whose sum is σ = 203003120922. Its totient is φ = 203003120920.

The previous prime is 203003120899. The next prime is 203003120923. The reversal of 203003120921 is 129021300302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 178473296521 + 24529824400 = 422461^2 + 156620^2 .

It is a cyclic number.

It is not a de Polignac number, because 203003120921 - 2⁶ = 203003120857 is a prime.

It is a super-2 number, since 2×203003120921² (a number of 23 digits) contains 22 as substring.

Together with 203003120923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (203003120923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101501560460 + 101501560461.

It is an arithmetic number, because the mean of its divisors is an integer number (101501560461).

Almost surely, 2^203003120921 is an apocalyptic number.

It is an amenable number.

203003120921 is a deficient number, since it is larger than the sum of its proper divisors (1).

203003120921 is an equidigital number, since it uses as much as digits as its factorization.

203003120921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 23.

The spelling of 203003120921 in words is "two hundred three billion, three million, one hundred twenty thousand, nine hundred twenty-one".