21240413500351 has 2 divisors, whose sum is σ = 21240413500352. Its totient is φ = 21240413500350.

The previous prime is 21240413500309. The next prime is 21240413500363. The reversal of 21240413500351 is 15300531404212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21240413500351 - 2⁹ = 21240413499839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21240413500651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10620206750175 + 10620206750176.

It is an arithmetic number, because the mean of its divisors is an integer number (10620206750176).

Almost surely, 2^{21240413500351} is an apocalyptic number.

21240413500351 is a deficient number, since it is larger than the sum of its proper divisors (1).

21240413500351 is an equidigital number, since it uses as much as digits as its factorization.

21240413500351 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 21240413500351 its reverse (15300531404212), we get a palindrome (36540944904563).

The spelling of 21240413500351 in words is "twenty-one trillion, two hundred forty billion, four hundred thirteen million, five hundred thousand, three hundred fifty-one".