21354335369 has 2 divisors, whose sum is σ = 21354335370. Its totient is φ = 21354335368.

The previous prime is 21354335309. The next prime is 21354335381. The reversal of 21354335369 is 96353345312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11366331769 + 9988003600 = 106613^2 + 99940^2 .

It is a cyclic number.

It is not a de Polignac number, because 21354335369 - 2⁸ = 21354335113 is a prime.

It is a super-2 number, since 2×21354335369² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21354335309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10677167684 + 10677167685.

It is an arithmetic number, because the mean of its divisors is an integer number (10677167685).

Almost surely, 2^21354335369 is an apocalyptic number.

It is an amenable number.

21354335369 is a deficient number, since it is larger than the sum of its proper divisors (1).

21354335369 is an equidigital number, since it uses as much as digits as its factorization.

21354335369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 874800, while the sum is 44.

The spelling of 21354335369 in words is "twenty-one billion, three hundred fifty-four million, three hundred thirty-five thousand, three hundred sixty-nine".