27453998521 has 4 divisors (see below), whose sum is σ = 27596247412. Its totient is φ = 27311749632.

The previous prime is 27453998497. The next prime is 27453998573. The reversal of 27453998521 is 12589935472.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1994604921 + 25459393600 = 44661^2 + 159560^2 .

It is a cyclic number.

It is not a de Polignac number, because 27453998521 - 2¹⁵ = 27453965753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27453998021) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 71124156 + ... + 71124541.

It is an arithmetic number, because the mean of its divisors is an integer number (6899061853).

Almost surely, 2^27453998521 is an apocalyptic number.

It is an amenable number.

27453998521 is a deficient number, since it is larger than the sum of its proper divisors (142248891).

27453998521 is a wasteful number, since it uses less digits than its factorization.

27453998521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142248890.

The product of its digits is 5443200, while the sum is 55.

The spelling of 27453998521 in words is "twenty-seven billion, four hundred fifty-three million, nine hundred ninety-eight thousand, five hundred twenty-one".