21145740186317 has 2 divisors, whose sum is σ = 21145740186318. Its totient is φ = 21145740186316.

The previous prime is 21145740186299. The next prime is 21145740186353. The reversal of 21145740186317 is 71368104754112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13810818796681 + 7334921389636 = 3716291^2 + 2708306^2 .

It is a cyclic number.

It is not a de Polignac number, because 21145740186317 - 2⁶ = 21145740186253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21145740186377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10572870093158 + 10572870093159.

It is an arithmetic number, because the mean of its divisors is an integer number (10572870093159).

Almost surely, 2^{21145740186317} is an apocalyptic number.

It is an amenable number.

21145740186317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21145740186317 is an equidigital number, since it uses as much as digits as its factorization.

21145740186317 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1128960, while the sum is 50.

The spelling of 21145740186317 in words is "twenty-one trillion, one hundred forty-five billion, seven hundred forty million, one hundred eighty-six thousand, three hundred seventeen".