21302461004509 has 2 divisors, whose sum is σ = 21302461004510. Its totient is φ = 21302461004508.

The previous prime is 21302461004459. The next prime is 21302461004597. The reversal of 21302461004509 is 90540016420312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13436696672100 + 7865764332409 = 3665610^2 + 2804597^2 .

It is a cyclic number.

It is not a de Polignac number, because 21302461004509 - 2⁹ = 21302461003997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21302461004309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651230502254 + 10651230502255.

It is an arithmetic number, because the mean of its divisors is an integer number (10651230502255).

Almost surely, 2^{21302461004509} is an apocalyptic number.

It is an amenable number.

21302461004509 is a deficient number, since it is larger than the sum of its proper divisors (1).

21302461004509 is an equidigital number, since it uses as much as digits as its factorization.

21302461004509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 37.

The spelling of 21302461004509 in words is "twenty-one trillion, three hundred two billion, four hundred sixty-one million, four thousand, five hundred nine".