21001420322347 has 2 divisors, whose sum is σ = 21001420322348. Its totient is φ = 21001420322346.

The previous prime is 21001420322321. The next prime is 21001420322447. The reversal of 21001420322347 is 74322302410012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21001420322347 - 2¹¹ = 21001420320299 is a prime.

It is not a weakly prime, because it can be changed into another prime (21001420322447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500710161173 + 10500710161174.

It is an arithmetic number, because the mean of its divisors is an integer number (10500710161174).

Almost surely, 2^{21001420322347} is an apocalyptic number.

21001420322347 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001420322347 is an equidigital number, since it uses as much as digits as its factorization.

21001420322347 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 31.

Adding to 21001420322347 its reverse (74322302410012), we get a palindrome (95323722732359).

The spelling of 21001420322347 in words is "twenty-one trillion, one billion, four hundred twenty million, three hundred twenty-two thousand, three hundred forty-seven".