21605255130 has 32 divisors (see below), whose sum is σ = 52182895104. Its totient is φ = 5724703296.

The previous prime is 21605255059. The next prime is 21605255141. The reversal of 21605255130 is 3155250612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

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 in 15 ways as a sum of consecutive naturals, for example, 2288842 + ... + 2298261.

It is an arithmetic number, because the mean of its divisors is an integer number (1630715472).

Almost surely, 2^21605255130 is an apocalyptic number.

21605255130 is an abundant number, since it is smaller than the sum of its proper divisors (30577639974).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21605255130 is a wasteful number, since it uses less digits than its factorization.

21605255130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4587270.

The product of its (nonzero) digits is 9000, while the sum is 30.

The spelling of 21605255130 in words is "twenty-one billion, six hundred five million, two hundred fifty-five thousand, one hundred thirty".