21224124545 has 16 divisors (see below), whose sum is σ = 27433183680. Its totient is φ = 15670294464.

The previous prime is 21224124533. The next prime is 21224124563. The reversal of 21224124545 is 54542142212.

It is a cyclic number.

It is not a de Polignac number, because 21224124545 - 2⁸ = 21224124289 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, 361886 + ... + 416424.

It is an arithmetic number, because the mean of its divisors is an integer number (1714573980).

Almost surely, 2^21224124545 is an apocalyptic number.

It is an amenable number.

21224124545 is a deficient number, since it is larger than the sum of its proper divisors (6209059135).

21224124545 is a wasteful number, since it uses less digits than its factorization.

21224124545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60544.

The product of its digits is 25600, while the sum is 32.

Adding to 21224124545 its reverse (54542142212), we get a palindrome (75766266757).

The spelling of 21224124545 in words is "twenty-one billion, two hundred twenty-four million, one hundred twenty-four thousand, five hundred forty-five".