21302515441 has 2 divisors, whose sum is σ = 21302515442. Its totient is φ = 21302515440.

The previous prime is 21302515393. The next prime is 21302515447. The reversal of 21302515441 is 14451520312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17232075441 + 4070440000 = 131271^2 + 63800^2 .

It is a cyclic number.

It is not a de Polignac number, because 21302515441 - 2¹³ = 21302507249 is a prime.

It is a super-3 number, since 3×21302515441³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (21302515447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651257720 + 10651257721.

It is an arithmetic number, because the mean of its divisors is an integer number (10651257721).

Almost surely, 2^21302515441 is an apocalyptic number.

It is an amenable number.

21302515441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21302515441 is an equidigital number, since it uses as much as digits as its factorization.

21302515441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 28.

The spelling of 21302515441 in words is "twenty-one billion, three hundred two million, five hundred fifteen thousand, four hundred forty-one".