21335318429 has 2 divisors, whose sum is σ = 21335318430. Its totient is φ = 21335318428.

The previous prime is 21335318419. The next prime is 21335318441. The reversal of 21335318429 is 92481353312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20135042404 + 1200276025 = 141898^2 + 34645^2 .

It is a cyclic number.

It is not a de Polignac number, because 21335318429 - 2⁴ = 21335318413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21335318419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10667659214 + 10667659215.

It is an arithmetic number, because the mean of its divisors is an integer number (10667659215).

Almost surely, 2^21335318429 is an apocalyptic number.

It is an amenable number.

21335318429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21335318429 is an equidigital number, since it uses as much as digits as its factorization.

21335318429 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 41.

The spelling of 21335318429 in words is "twenty-one billion, three hundred thirty-five million, three hundred eighteen thousand, four hundred twenty-nine".