2121253665253 has 4 divisors (see below), whose sum is σ = 2121782264748. Its totient is φ = 2120725065760.

The previous prime is 2121253665203. The next prime is 2121253665257. The reversal of 2121253665253 is 3525663521212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1338607348324 + 782646316929 = 1156982^2 + 884673^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121253665253 is a prime.

It is a super-2 number, since 2×2121253665253² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121253665257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264293728 + ... + 264301753.

It is an arithmetic number, because the mean of its divisors is an integer number (530445566187).

Almost surely, 2^{2121253665253} is an apocalyptic number.

It is an amenable number.

2121253665253 is a deficient number, since it is larger than the sum of its proper divisors (528599495).

2121253665253 is an equidigital number, since it uses as much as digits as its factorization.

2121253665253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528599494.

The product of its digits is 648000, while the sum is 43.

The spelling of 2121253665253 in words is "two trillion, one hundred twenty-one billion, two hundred fifty-three million, six hundred sixty-five thousand, two hundred fifty-three".