21430836481 has 2 divisors, whose sum is σ = 21430836482. Its totient is φ = 21430836480.

The previous prime is 21430836473. The next prime is 21430836491. The reversal of 21430836481 is 18463803412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20990214400 + 440622081 = 144880^2 + 20991^2 .

It is a cyclic number.

It is not a de Polignac number, because 21430836481 - 2³ = 21430836473 is a prime.

It is a super-2 number, since 2×21430836481² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21430836491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10715418240 + 10715418241.

It is an arithmetic number, because the mean of its divisors is an integer number (10715418241).

Almost surely, 2^21430836481 is an apocalyptic number.

It is an amenable number.

21430836481 is a deficient number, since it is larger than the sum of its proper divisors (1).

21430836481 is an equidigital number, since it uses as much as digits as its factorization.

21430836481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 110592, while the sum is 40.

The spelling of 21430836481 in words is "twenty-one billion, four hundred thirty million, eight hundred thirty-six thousand, four hundred eighty-one".