21080555587 has 8 divisors (see below), whose sum is σ = 25945299296. Its totient is φ = 16679120832.

The previous prime is 21080555581. The next prime is 21080555621. The reversal of 21080555587 is 78555508012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21080555587 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21080555581) 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 7 ways as a sum of consecutive naturals, for example, 115827138 + ... + 115827319.

It is an arithmetic number, because the mean of its divisors is an integer number (3243162412).

Almost surely, 2^21080555587 is an apocalyptic number.

21080555587 is a deficient number, since it is larger than the sum of its proper divisors (4864743709).

21080555587 is a wasteful number, since it uses less digits than its factorization.

21080555587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231654477.

The product of its (nonzero) digits is 560000, while the sum is 46.

The spelling of 21080555587 in words is "twenty-one billion, eighty million, five hundred fifty-five thousand, five hundred eighty-seven".