21252134534261 has 2 divisors, whose sum is σ = 21252134534262. Its totient is φ = 21252134534260.

The previous prime is 21252134534227. The next prime is 21252134534321. The reversal of 21252134534261 is 16243543125212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20478394393636 + 773740140625 = 4525306^2 + 879625^2 .

It is a cyclic number.

It is not a de Polignac number, because 21252134534261 - 2³⁴ = 21234954665077 is a prime.

It is a super-2 number, since 2×21252134534261² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21252134531261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10626067267130 + 10626067267131.

It is an arithmetic number, because the mean of its divisors is an integer number (10626067267131).

Almost surely, 2^{21252134534261} is an apocalyptic number.

It is an amenable number.

21252134534261 is a deficient number, since it is larger than the sum of its proper divisors (1).

21252134534261 is an equidigital number, since it uses as much as digits as its factorization.

21252134534261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345600, while the sum is 41.

Adding to 21252134534261 its reverse (16243543125212), we get a palindrome (37495677659473).

The spelling of 21252134534261 in words is "twenty-one trillion, two hundred fifty-two billion, one hundred thirty-four million, five hundred thirty-four thousand, two hundred sixty-one".