203121323257 has 2 divisors, whose sum is σ = 203121323258. Its totient is φ = 203121323256.

The previous prime is 203121323243. The next prime is 203121323267. The reversal of 203121323257 is 752323121302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180139976041 + 22981347216 = 424429^2 + 151596^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-203121323257 is a prime.

It is not a weakly prime, because it can be changed into another prime (203121323267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101560661628 + 101560661629.

It is an arithmetic number, because the mean of its divisors is an integer number (101560661629).

Almost surely, 2^203121323257 is an apocalyptic number.

It is an amenable number.

203121323257 is a deficient number, since it is larger than the sum of its proper divisors (1).

203121323257 is an equidigital number, since it uses as much as digits as its factorization.

203121323257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 31.

Adding to 203121323257 its reverse (752323121302), we get a palindrome (955444444559).

The spelling of 203121323257 in words is "two hundred three billion, one hundred twenty-one million, three hundred twenty-three thousand, two hundred fifty-seven".