21545002105 has 16 divisors (see below), whose sum is σ = 29863448064. Its totient is φ = 14747380480.

The previous prime is 21545002081. The next prime is 21545002133. The reversal of 21545002105 is 50120054512.

It is not a de Polignac number, because 21545002105 - 2⁷ = 21545001977 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 21545002105.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11520457 + ... + 11522326.

It is an arithmetic number, because the mean of its divisors is an integer number (1866465504).

Almost surely, 2^21545002105 is an apocalyptic number.

It is an amenable number.

21545002105 is a deficient number, since it is larger than the sum of its proper divisors (8318445959).

21545002105 is a wasteful number, since it uses less digits than its factorization.

21545002105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23042816.

The product of its (nonzero) digits is 2000, while the sum is 25.

Adding to 21545002105 its reverse (50120054512), we get a palindrome (71665056617).

The spelling of 21545002105 in words is "twenty-one billion, five hundred forty-five million, two thousand, one hundred five".