21554451304 has 8 divisors (see below), whose sum is σ = 40414596210. Its totient is φ = 10777225648.

The previous prime is 21554451239. The next prime is 21554451319. The reversal of 21554451304 is 40315445512.

It can be written as a sum of positive squares in only one way, i.e., 18824388804 + 2730062500 = 137202^2 + 52250^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 21554451304.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1347153199 + ... + 1347153214.

Almost surely, 2^21554451304 is an apocalyptic number.

It is an amenable number.

21554451304 is a deficient number, since it is larger than the sum of its proper divisors (18860144906).

21554451304 is a wasteful number, since it uses less digits than its factorization.

21554451304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2694306419 (or 2694306415 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 34.

Adding to 21554451304 its reverse (40315445512), we get a palindrome (61869896816).

The spelling of 21554451304 in words is "twenty-one billion, five hundred fifty-four million, four hundred fifty-one thousand, three hundred four".