21005345335 has 32 divisors (see below), whose sum is σ = 28043850240. Its totient is φ = 14999040000.

The previous prime is 21005345311. The next prime is 21005345341. The reversal of 21005345335 is 53354350012.

It is not a de Polignac number, because 21005345335 - 2²³ = 20996956727 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a junction number, because it is equal to n+sod(n) for n = 21005345297 and 21005345306.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2996835 + ... + 3003835.

It is an arithmetic number, because the mean of its divisors is an integer number (876370320).

Almost surely, 2^21005345335 is an apocalyptic number.

21005345335 is a deficient number, since it is larger than the sum of its proper divisors (7038504905).

21005345335 is a wasteful number, since it uses less digits than its factorization.

21005345335 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8539.

The product of its (nonzero) digits is 27000, while the sum is 31.

Adding to 21005345335 its reverse (53354350012), we get a palindrome (74359695347).

It can be divided in two parts, 2100 and 5345335, that added together give a palindrome (5347435).

The spelling of 21005345335 in words is "twenty-one billion, five million, three hundred forty-five thousand, three hundred thirty-five".