21535650413 has 2 divisors, whose sum is σ = 21535650414. Its totient is φ = 21535650412.

The previous prime is 21535650403. The next prime is 21535650449. The reversal of 21535650413 is 31405653512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17800362724 + 3735287689 = 133418^2 + 61117^2 .

It is a cyclic number.

It is not a de Polignac number, because 21535650413 - 2²² = 21531456109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21535650403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10767825206 + 10767825207.

It is an arithmetic number, because the mean of its divisors is an integer number (10767825207).

Almost surely, 2^21535650413 is an apocalyptic number.

It is an amenable number.

21535650413 is a deficient number, since it is larger than the sum of its proper divisors (1).

21535650413 is an equidigital number, since it uses as much as digits as its factorization.

21535650413 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54000, while the sum is 35.

The spelling of 21535650413 in words is "twenty-one billion, five hundred thirty-five million, six hundred fifty thousand, four hundred thirteen".