21030330122981 has 2 divisors, whose sum is σ = 21030330122982. Its totient is φ = 21030330122980.

The previous prime is 21030330122953. The next prime is 21030330123053. The reversal of 21030330122981 is 18922103303012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14652856689025 + 6377473433956 = 3827905^2 + 2525366^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030330122981 - 2³⁰ = 21029256381157 is a prime.

It is a super-2 number, since 2×21030330122981² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21030330122881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515165061490 + 10515165061491.

It is an arithmetic number, because the mean of its divisors is an integer number (10515165061491).

Almost surely, 2^{21030330122981} is an apocalyptic number.

It is an amenable number.

21030330122981 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030330122981 is an equidigital number, since it uses as much as digits as its factorization.

21030330122981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 35.

Adding to 21030330122981 its reverse (18922103303012), we get a palindrome (39952433425993).

The spelling of 21030330122981 in words is "twenty-one trillion, thirty billion, three hundred thirty million, one hundred twenty-two thousand, nine hundred eighty-one".