21252561435205 has 8 divisors (see below), whose sum is σ = 25503648602112. Its totient is φ = 17001665894928.

The previous prime is 21252561435181. The next prime is 21252561435263. The reversal of 21252561435205 is 50253416525212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21252561435205 - 2²³ = 21252553046597 is a prime.

It is a super-3 number, since 3×21252561435205³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47662549 + ... + 48106378.

It is an arithmetic number, because the mean of its divisors is an integer number (3187956075264).

Almost surely, 2^{21252561435205} is an apocalyptic number.

It is an amenable number.

21252561435205 is a deficient number, since it is larger than the sum of its proper divisors (4251087166907).

21252561435205 is an equidigital number, since it uses as much as digits as its factorization.

21252561435205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95813315.

The product of its (nonzero) digits is 720000, while the sum is 43.

The spelling of 21252561435205 in words is "twenty-one trillion, two hundred fifty-two billion, five hundred sixty-one million, four hundred thirty-five thousand, two hundred five".