21112202240257 has 2 divisors, whose sum is σ = 21112202240258. Its totient is φ = 21112202240256.

The previous prime is 21112202240251. The next prime is 21112202240267. The reversal of 21112202240257 is 75204220221112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21043220369521 + 68981870736 = 4587289^2 + 262644^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112202240257 - 2¹¹ = 21112202238209 is a prime.

It is not a weakly prime, because it can be changed into another prime (21112202240251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556101120128 + 10556101120129.

It is an arithmetic number, because the mean of its divisors is an integer number (10556101120129).

Almost surely, 2^{21112202240257} is an apocalyptic number.

It is an amenable number.

21112202240257 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112202240257 is an equidigital number, since it uses as much as digits as its factorization.

21112202240257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8960, while the sum is 31.

Adding to 21112202240257 its reverse (75204220221112), we get a palindrome (96316422461369).

The spelling of 21112202240257 in words is "twenty-one trillion, one hundred twelve billion, two hundred two million, two hundred forty thousand, two hundred fifty-seven".