21554550544 has 20 divisors (see below), whose sum is σ = 41764747024. Its totient is φ = 10776551328.

The previous prime is 21554550541. The next prime is 21554550553. The reversal of 21554550544 is 44505545512.

It is a junction number, because it is equal to n+sod(n) for n = 21554550497 and 21554550506.

It is not an unprimeable number, because it can be changed into a prime (21554550541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264739 + ... + 336445.

Almost surely, 2^21554550544 is an apocalyptic number.

It is an amenable number.

21554550544 is a deficient number, since it is larger than the sum of its proper divisors (20210196480).

21554550544 is a wasteful number, since it uses less digits than its factorization.

21554550544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90502 (or 90496 counting only the distinct ones).

The product of its (nonzero) digits is 400000, while the sum is 40.

The spelling of 21554550544 in words is "twenty-one billion, five hundred fifty-four million, five hundred fifty thousand, five hundred forty-four".