21355352524305 has 12 divisors (see below), whose sum is σ = 37015944375540. Its totient is φ = 11389521346272.

The previous prime is 21355352524301. The next prime is 21355352524357. The reversal of 21355352524305 is 50342525355312.

21355352524305 is a `hidden beast` number, since 2 + 1 + 3 + 55 + 352 + 5 + 243 + 0 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16174489149504 + 5180863374801 = 4021752^2 + 2276151^2 .

It is not a de Polignac number, because 21355352524305 - 2² = 21355352524301 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 474563389429 = 21355352524305 / (2 + 1 + 3 + 5 + 5 + 3 + 5 + 2 + 5 + 2 + 4 + 3 + 0 + 5).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21355352524301) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 237281694670 + ... + 237281694759.

It is an arithmetic number, because the mean of its divisors is an integer number (3084662031295).

Almost surely, 2^{21355352524305} is an apocalyptic number.

It is an amenable number.

21355352524305 is a deficient number, since it is larger than the sum of its proper divisors (15660591851235).

21355352524305 is a wasteful number, since it uses less digits than its factorization.

21355352524305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474563389440 (or 474563389437 counting only the distinct ones).

The product of its (nonzero) digits is 2700000, while the sum is 45.

Adding to 21355352524305 its reverse (50342525355312), we get a palindrome (71697877879617).

The spelling of 21355352524305 in words is "twenty-one trillion, three hundred fifty-five billion, three hundred fifty-two million, five hundred twenty-four thousand, three hundred five".