21343215138451 has 2 divisors, whose sum is σ = 21343215138452. Its totient is φ = 21343215138450.

The previous prime is 21343215138433. The next prime is 21343215138481. The reversal of 21343215138451 is 15483151234312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21343215138451 - 2²⁷ = 21343080920723 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21343215138398 and 21343215138407.

It is not a weakly prime, because it can be changed into another prime (21343215138481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671607569225 + 10671607569226.

It is an arithmetic number, because the mean of its divisors is an integer number (10671607569226).

Almost surely, 2^{21343215138451} is an apocalyptic number.

21343215138451 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343215138451 is an equidigital number, since it uses as much as digits as its factorization.

21343215138451 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 345600, while the sum is 43.

The spelling of 21343215138451 in words is "twenty-one trillion, three hundred forty-three billion, two hundred fifteen million, one hundred thirty-eight thousand, four hundred fifty-one".