21404004569 has 2 divisors, whose sum is σ = 21404004570. Its totient is φ = 21404004568.

The previous prime is 21404004511. The next prime is 21404004617. The reversal of 21404004569 is 96540040412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11499774169 + 9904230400 = 107237^2 + 99520^2 .

It is a cyclic number.

It is not a de Polignac number, because 21404004569 - 2²⁴ = 21387227353 is a prime.

It is a super-2 number, since 2×21404004569² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21404024569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10702002284 + 10702002285.

It is an arithmetic number, because the mean of its divisors is an integer number (10702002285).

Almost surely, 2^21404004569 is an apocalyptic number.

It is an amenable number.

21404004569 is a deficient number, since it is larger than the sum of its proper divisors (1).

21404004569 is an equidigital number, since it uses as much as digits as its factorization.

21404004569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34560, while the sum is 35.

The spelling of 21404004569 in words is "twenty-one billion, four hundred four million, four thousand, five hundred sixty-nine".