21251103213413 has 2 divisors, whose sum is σ = 21251103213414. Its totient is φ = 21251103213412.

The previous prime is 21251103213343. The next prime is 21251103213427. The reversal of 21251103213413 is 31431230115212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14591307500449 + 6659795712964 = 3819857^2 + 2580658^2 .

It is a cyclic number.

It is not a de Polignac number, because 21251103213413 - 2¹⁰ = 21251103212389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21251103213313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10625551606706 + 10625551606707.

It is an arithmetic number, because the mean of its divisors is an integer number (10625551606707).

Almost surely, 2^{21251103213413} is an apocalyptic number.

It is an amenable number.

21251103213413 is a deficient number, since it is larger than the sum of its proper divisors (1).

21251103213413 is an equidigital number, since it uses as much as digits as its factorization.

21251103213413 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 29.

Adding to 21251103213413 its reverse (31431230115212), we get a palindrome (52682333328625).

The spelling of 21251103213413 in words is "twenty-one trillion, two hundred fifty-one billion, one hundred three million, two hundred thirteen thousand, four hundred thirteen".