21515414452205 has 4 divisors (see below), whose sum is σ = 25818497342652. Its totient is φ = 17212331561760.

The previous prime is 21515414452163. The next prime is 21515414452241. The reversal of 21515414452205 is 50225441451512.

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 5141438340676 + 16373976111529 = 2267474^2 + 4046477^2 .

It is not a de Polignac number, because 21515414452205 - 2²⁰ = 21515413403629 is a prime.

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 3 ways as a sum of consecutive naturals, for example, 2151541445216 + ... + 2151541445225.

It is an arithmetic number, because the mean of its divisors is an integer number (6454624335663).

Almost surely, 2^{21515414452205} is an apocalyptic number.

It is an amenable number.

21515414452205 is a deficient number, since it is larger than the sum of its proper divisors (4303082890447).

21515414452205 is an equidigital number, since it uses as much as digits as its factorization.

21515414452205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4303082890446.

The product of its (nonzero) digits is 320000, while the sum is 41.

The spelling of 21515414452205 in words is "twenty-one trillion, five hundred fifteen billion, four hundred fourteen million, four hundred fifty-two thousand, two hundred five".