21051450253 has 2 divisors, whose sum is σ = 21051450254. Its totient is φ = 21051450252.

The previous prime is 21051450191. The next prime is 21051450269. The reversal of 21051450253 is 35205415012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16174243684 + 4877206569 = 127178^2 + 69837^2 .

It is a cyclic number.

It is not a de Polignac number, because 21051450253 - 2²⁹ = 20514579341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21051450053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10525725126 + 10525725127.

It is an arithmetic number, because the mean of its divisors is an integer number (10525725127).

Almost surely, 2^21051450253 is an apocalyptic number.

It is an amenable number.

21051450253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21051450253 is an equidigital number, since it uses as much as digits as its factorization.

21051450253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6000, while the sum is 28.

Adding to 21051450253 its reverse (35205415012), we get a palindrome (56256865265).

The spelling of 21051450253 in words is "twenty-one billion, fifty-one million, four hundred fifty thousand, two hundred fifty-three".