21051320045 has 8 divisors (see below), whose sum is σ = 28870381824. Its totient is φ = 14435190864.

The previous prime is 21051320039. The next prime is 21051320053. The reversal of 21051320045 is 54002315012.

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 21051320045 - 2⁶ = 21051319981 is a prime.

It is a super-3 number, since 3×21051320045³ (a number of 32 digits) contains 333 as substring.

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 21051320045.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 300733109 + ... + 300733178.

It is an arithmetic number, because the mean of its divisors is an integer number (3608797728).

Almost surely, 2^21051320045 is an apocalyptic number.

It is an amenable number.

21051320045 is a deficient number, since it is larger than the sum of its proper divisors (7819061779).

21051320045 is an equidigital number, since it uses as much as digits as its factorization.

21051320045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601466299.

The product of its (nonzero) digits is 1200, while the sum is 23.

Adding to 21051320045 its reverse (54002315012), we get a palindrome (75053635057).

The spelling of 21051320045 in words is "twenty-one billion, fifty-one million, three hundred twenty thousand, forty-five".