21211120253 has 2 divisors, whose sum is σ = 21211120254. Its totient is φ = 21211120252.

The previous prime is 21211120207. The next prime is 21211120309. The reversal of 21211120253 is 35202111212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20787295684 + 423824569 = 144178^2 + 20587^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211120253 - 2²⁰ = 21210071677 is a prime.

It is a super-3 number, since 3×21211120253³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21211123253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605560126 + 10605560127.

It is an arithmetic number, because the mean of its divisors is an integer number (10605560127).

Almost surely, 2^21211120253 is an apocalyptic number.

It is an amenable number.

21211120253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211120253 is an equidigital number, since it uses as much as digits as its factorization.

21211120253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 21211120253 its reverse (35202111212), we get a palindrome (56413231465).

The spelling of 21211120253 in words is "twenty-one billion, two hundred eleven million, one hundred twenty thousand, two hundred fifty-three".