21815581130 has 16 divisors (see below), whose sum is σ = 44877767040. Its totient is φ = 7479627792.

The previous prime is 21815581129. The next prime is 21815581157. The reversal of 21815581130 is 3118551812.

It is a super-2 number, since 2×21815581130² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a Curzon number.

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 7 ways as a sum of consecutive naturals, for example, 155825510 + ... + 155825649.

It is an arithmetic number, because the mean of its divisors is an integer number (2804860440).

Almost surely, 2^21815581130 is an apocalyptic number.

21815581130 is an abundant number, since it is smaller than the sum of its proper divisors (23062185910).

21815581130 is a wasteful number, since it uses less digits than its factorization.

21815581130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311651173.

The product of its (nonzero) digits is 9600, while the sum is 35.

The spelling of 21815581130 in words is "twenty-one billion, eight hundred fifteen million, five hundred eighty-one thousand, one hundred thirty".