21021021000047 has 2 divisors, whose sum is σ = 21021021000048. Its totient is φ = 21021021000046.

The previous prime is 21021020999977. The next prime is 21021021000121. The reversal of 21021021000047 is 74000012012012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21021021000047 - 2¹⁴ = 21021020983663 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021020999992 and 21021021000028.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21021021000247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510510500023 + 10510510500024.

It is an arithmetic number, because the mean of its divisors is an integer number (10510510500024).

Almost surely, 2^{21021021000047} is an apocalyptic number.

21021021000047 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021021000047 is an equidigital number, since it uses as much as digits as its factorization.

21021021000047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 224, while the sum is 20.

Adding to 21021021000047 its reverse (74000012012012), we get a palindrome (95021033012059).

The spelling of 21021021000047 in words is "twenty-one trillion, twenty-one billion, twenty-one million, forty-seven", and thus it is an aban number and an uban number.