21215422045 has 8 divisors (see below), whose sum is σ = 26146574424. Its totient is φ = 16513625664.

The previous prime is 21215422037. The next prime is 21215422049. The reversal of 21215422045 is 54022451212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10037434969 + 11177987076 = 100187^2 + 105726^2 .

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 21215422045 - 2³ = 21215422037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21215422049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57338794 + ... + 57339163.

It is an arithmetic number, because the mean of its divisors is an integer number (3268321803).

Almost surely, 2^21215422045 is an apocalyptic number.

It is an amenable number.

21215422045 is a deficient number, since it is larger than the sum of its proper divisors (4931152379).

21215422045 is a wasteful number, since it uses less digits than its factorization.

21215422045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114677999.

The product of its (nonzero) digits is 6400, while the sum is 28.

Adding to 21215422045 its reverse (54022451212), we get a palindrome (75237873257).

The spelling of 21215422045 in words is "twenty-one billion, two hundred fifteen million, four hundred twenty-two thousand, forty-five".