21001120102253 has 2 divisors, whose sum is σ = 21001120102254. Its totient is φ = 21001120102252.

The previous prime is 21001120102181. The next prime is 21001120102309. The reversal of 21001120102253 is 35220102110012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11836441610569 + 9164678491684 = 3440413^2 + 3027322^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001120102253 - 2¹² = 21001120098157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001120104253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500560051126 + 10500560051127.

It is an arithmetic number, because the mean of its divisors is an integer number (10500560051127).

Almost surely, 2^{21001120102253} is an apocalyptic number.

It is an amenable number.

21001120102253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001120102253 is an equidigital number, since it uses as much as digits as its factorization.

21001120102253 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21001120102253 its reverse (35220102110012), we get a palindrome (56221222212265).

The spelling of 21001120102253 in words is "twenty-one trillion, one billion, one hundred twenty million, one hundred two thousand, two hundred fifty-three".