21452221345 has 16 divisors (see below), whose sum is σ = 25892536320. Its totient is φ = 17061969600.

The previous prime is 21452221229. The next prime is 21452221363. The reversal of 21452221345 is 54312225412.

It is a happy number.

It is not a de Polignac number, because 21452221345 - 2⁹ = 21452220833 is a prime.

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, 1932160 + ... + 1943230.

It is an arithmetic number, because the mean of its divisors is an integer number (1618283520).

Almost surely, 2^21452221345 is an apocalyptic number.

It is an amenable number.

21452221345 is a deficient number, since it is larger than the sum of its proper divisors (4440314975).

21452221345 is a wasteful number, since it uses less digits than its factorization.

21452221345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13296.

The product of its digits is 19200, while the sum is 31.

Adding to 21452221345 its reverse (54312225412), we get a palindrome (75764446757).

The spelling of 21452221345 in words is "twenty-one billion, four hundred fifty-two million, two hundred twenty-one thousand, three hundred forty-five".