21361743523 has 2 divisors, whose sum is σ = 21361743524. Its totient is φ = 21361743522.

The previous prime is 21361743509. The next prime is 21361743527. The reversal of 21361743523 is 32534716312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21361743523 - 2¹³ = 21361735331 is a prime.

It is not a weakly prime, because it can be changed into another prime (21361743527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10680871761 + 10680871762.

It is an arithmetic number, because the mean of its divisors is an integer number (10680871762).

Almost surely, 2^21361743523 is an apocalyptic number.

21361743523 is a deficient number, since it is larger than the sum of its proper divisors (1).

21361743523 is an equidigital number, since it uses as much as digits as its factorization.

21361743523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 37.

The spelling of 21361743523 in words is "twenty-one billion, three hundred sixty-one million, seven hundred forty-three thousand, five hundred twenty-three".