21544551445 has 16 divisors (see below), whose sum is σ = 26057116800. Its totient is φ = 17100140224.

The previous prime is 21544551437. The next prime is 21544551493. The reversal of 21544551445 is 54415544512.

It is a cyclic number.

It is not a de Polignac number, because 21544551445 - 2³ = 21544551437 is a prime.

It is a super-3 number, since 3×21544551445³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21544551398 and 21544551407.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 644514 + ... + 677116.

It is an arithmetic number, because the mean of its divisors is an integer number (1628569800).

Almost surely, 2^21544551445 is an apocalyptic number.

It is an amenable number.

21544551445 is a deficient number, since it is larger than the sum of its proper divisors (4512565355).

21544551445 is a wasteful number, since it uses less digits than its factorization.

21544551445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33644.

The product of its digits is 320000, while the sum is 40.

The spelling of 21544551445 in words is "twenty-one billion, five hundred forty-four million, five hundred fifty-one thousand, four hundred forty-five".