21224545441546 has 16 divisors (see below), whose sum is σ = 31910857965000. Its totient is φ = 10587593576448.

The previous prime is 21224545441537. The next prime is 21224545441553. The reversal of 21224545441546 is 64514454542212.

It can be written as a sum of positive squares in 4 ways, for example, as 8129997229225 + 13094548212321 = 2851315^2 + 3618639^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21224545441546.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66739000 + ... + 67056268.

Almost surely, 2^{21224545441546} is an apocalyptic number.

21224545441546 is a deficient number, since it is larger than the sum of its proper divisors (10686312523454).

21224545441546 is a wasteful number, since it uses less digits than its factorization.

21224545441546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394953.

The product of its digits is 6144000, while the sum is 49.

Adding to 21224545441546 its reverse (64514454542212), we get a palindrome (85738999983758).

The spelling of 21224545441546 in words is "twenty-one trillion, two hundred twenty-four billion, five hundred forty-five million, four hundred forty-one thousand, five hundred forty-six".