21554445513 has 8 divisors (see below), whose sum is σ = 28885146048. Its totient is φ = 14296687664.

The previous prime is 21554445511. The next prime is 21554445527. The reversal of 21554445513 is 31554445512.

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

It is a cyclic number.

It is not a de Polignac number, because 21554445513 - 2¹ = 21554445511 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21554445511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18234981 + ... + 18236162.

It is an arithmetic number, because the mean of its divisors is an integer number (3610643256).

Almost surely, 2^21554445513 is an apocalyptic number.

It is an amenable number.

21554445513 is a deficient number, since it is larger than the sum of its proper divisors (7330700535).

21554445513 is a wasteful number, since it uses less digits than its factorization.

21554445513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36471343.

The product of its digits is 240000, while the sum is 39.

Subtracting 21554445513 from its reverse (31554445512), we obtain a palindrome (9999999999).

The spelling of 21554445513 in words is "twenty-one billion, five hundred fifty-four million, four hundred forty-five thousand, five hundred thirteen".