21235000445 has 4 divisors (see below), whose sum is σ = 25482000540. Its totient is φ = 16988000352.

The previous prime is 21235000427. The next prime is 21235000499. The reversal of 21235000445 is 54400053212.

It is a happy number.

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 16093967044 + 5141033401 = 126862^2 + 71701^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21235000445 is a prime.

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 3 ways as a sum of consecutive naturals, for example, 2123500040 + ... + 2123500049.

It is an arithmetic number, because the mean of its divisors is an integer number (6370500135).

Almost surely, 2^21235000445 is an apocalyptic number.

It is an amenable number.

21235000445 is a deficient number, since it is larger than the sum of its proper divisors (4247000095).

21235000445 is an equidigital number, since it uses as much as digits as its factorization.

21235000445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4247000094.

The product of its (nonzero) digits is 4800, while the sum is 26.

Adding to 21235000445 its reverse (54400053212), we get a palindrome (75635053657).

The spelling of 21235000445 in words is "twenty-one billion, two hundred thirty-five million, four hundred forty-five", and thus it is an aban number.