21452808329 has 4 divisors (see below), whose sum is σ = 21467574276. Its totient is φ = 21438042384.

The previous prime is 21452808313. The next prime is 21452808341. The reversal of 21452808329 is 92380825412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15738204304 + 5714604025 = 125452^2 + 75595^2 .

It is a cyclic number.

It is not a de Polignac number, because 21452808329 - 2⁴ = 21452808313 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21452808329.

It is not an unprimeable number, because it can be changed into a prime (21452801329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7380794 + ... + 7383699.

It is an arithmetic number, because the mean of its divisors is an integer number (5366893569).

Almost surely, 2^21452808329 is an apocalyptic number.

It is an amenable number.

21452808329 is a deficient number, since it is larger than the sum of its proper divisors (14765947).

21452808329 is a wasteful number, since it uses less digits than its factorization.

21452808329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14765946.

The product of its (nonzero) digits is 276480, while the sum is 44.

The spelling of 21452808329 in words is "twenty-one billion, four hundred fifty-two million, eight hundred eight thousand, three hundred twenty-nine".