21455452511554 has 8 divisors (see below), whose sum is σ = 32968134347148. Its totient is φ = 10466074395840.

The previous prime is 21455452511531. The next prime is 21455452511561. The reversal of 21455452511554 is 45511525455412.

It can be written as a sum of positive squares in 2 ways, for example, as 20473226820225 + 982225691329 = 4524735^2 + 991073^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21455452511498 and 21455452511507.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 130825929867 + ... + 130825930030.

Almost surely, 2^{21455452511554} is an apocalyptic number.

21455452511554 is a deficient number, since it is larger than the sum of its proper divisors (11512681835594).

21455452511554 is a wasteful number, since it uses less digits than its factorization.

21455452511554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261651859940.

The product of its digits is 4000000, while the sum is 49.

Adding to 21455452511554 its reverse (45511525455412), we get a palindrome (66966977966966).

The spelling of 21455452511554 in words is "twenty-one trillion, four hundred fifty-five billion, four hundred fifty-two million, five hundred eleven thousand, five hundred fifty-four".