203206205021 has 2 divisors, whose sum is σ = 203206205022. Its totient is φ = 203206205020.

The previous prime is 203206205003. The next prime is 203206205087. The reversal of 203206205021 is 120502602302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 103757428996 + 99448776025 = 322114^2 + 315355^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-203206205021 is a prime.

It is a super-2 number, since 2×203206205021² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (203206208021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101603102510 + 101603102511.

It is an arithmetic number, because the mean of its divisors is an integer number (101603102511).

Almost surely, 2^203206205021 is an apocalyptic number.

It is an amenable number.

203206205021 is a deficient number, since it is larger than the sum of its proper divisors (1).

203206205021 is an equidigital number, since it uses as much as digits as its factorization.

203206205021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 23.

Adding to 203206205021 its reverse (120502602302), we get a palindrome (323708807323).

The spelling of 203206205021 in words is "two hundred three billion, two hundred six million, two hundred five thousand, twenty-one".