21063126253 has 4 divisors (see below), whose sum is σ = 22683366748. Its totient is φ = 19442885760.

The previous prime is 21063126247. The next prime is 21063126257. The reversal of 21063126253 is 35262136012.

It is a happy number.

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 2323432804 + 18739693449 = 48202^2 + 136893^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21063126253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21063126257) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 810120228 + ... + 810120253.

It is an arithmetic number, because the mean of its divisors is an integer number (5670841687).

Almost surely, 2^21063126253 is an apocalyptic number.

It is an amenable number.

21063126253 is a deficient number, since it is larger than the sum of its proper divisors (1620240495).

21063126253 is a wasteful number, since it uses less digits than its factorization.

21063126253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1620240494.

The product of its (nonzero) digits is 12960, while the sum is 31.

The spelling of 21063126253 in words is "twenty-one billion, sixty-three million, one hundred twenty-six thousand, two hundred fifty-three".