21450103253 has 2 divisors, whose sum is σ = 21450103254. Its totient is φ = 21450103252.

The previous prime is 21450103231. The next prime is 21450103267. The reversal of 21450103253 is 35230105412.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17281205764 + 4168897489 = 131458^2 + 64567^2 .

It is a cyclic number.

It is not a de Polignac number, because 21450103253 - 2¹⁰ = 21450102229 is a prime.

It is a super-2 number, since 2×21450103253² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21450100253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10725051626 + 10725051627.

It is an arithmetic number, because the mean of its divisors is an integer number (10725051627).

Almost surely, 2^21450103253 is an apocalyptic number.

It is an amenable number.

21450103253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21450103253 is an equidigital number, since it uses as much as digits as its factorization.

21450103253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 26.

Adding to 21450103253 its reverse (35230105412), we get a palindrome (56680208665).

The spelling of 21450103253 in words is "twenty-one billion, four hundred fifty million, one hundred three thousand, two hundred fifty-three".